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Unusual photocarrier and coherent phonon dynamics behaviors of layered PdSe_(2)unveiled by ultrafast spectroscopy of the edge surface

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 143-152页

作者： Tiantian Yun Changfu Huo Jinluo cheng zhi-Bo Liu xiao-Qing Yan Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin 300071China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China GPL Photonics Laboratory Key Laboratory of Luminescence Science and TechnologyChinese Academy of Sciences&State Key Laboratory of Luminescence Science and ApplicationsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Layered materials exhibit different electronic and phonon properties along in-plane and out-of-plane directions;existing studies focus on their in-plane behaviors,and the influence of such anisotropies on the dynamics of photocarriers and phonons is ***,we fabricate layered PdSe_(2)crystals with flat edge surfaces and compare the time-resolved ultrafast spectroscopies on their basal and edge *** differences in the transient reflection spectroscopies reveal the inconsistent photocarrier and phonon dynamics behaviors on the two surfaces:the slow hot carrier relaxation process is accelerated and the thermoelasticity-induced longitudinal coherent acoustic phonon oscillation completely vanishes on the edge surface,as compared with the basal *** analysis reveals that the inconsistent hot carrier dynamics originate from the anisotropic properties of low-energy phonons in PdSe_(2),and the absence of phonon oscillation on the edge surface results from the wavevector-limited sensitivity of acoustic B_(1u)***,polarization-dependent spectroscopies indicate the diverse optical anisotropies beyond the in-plane of PdSe_(2).This work provides a new method to explore unique physical properties and modulate the optical anisotropy of layered materials.

关键词： PdSe_(2) ultrafast spectroscopy edge surface carrier dynamics coherent phonon oscillation anisotropy

Dual modification of LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2) cathode materials by K^(+) doping and Li_(3)PO_(4) coating for lithium ions batteries

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Rare Metals 2024年第7期43卷 3007-3018页

作者： Wei xiao Jia-Le Wang zhi-cheng Yi cheng-Jin Liu Chang Miao Yu Xin Shu-Qing Nie College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou 434023China

Li_(3)PO_(4)@Li_(0.99)K_(0.01)Ni_(0.83)Co_(0.11)Mn_(O.06)O_(2)(NCM-KP) cathode powders are synthesized via K^(+)doping in calcination processes and H_3PO_4 coating in sol-gel processes.K^(+) precisely enters into the lattice to widen the(003) plane to 0.4746 nm with a lower cationic disordered degree of 1.87%.Moreover,the surface residual lithium salts are treated by H_3PO_4 to generate a uniform Li_(3)PO_(4) coating layer of approximately 11.41 nm,which completely covers on the surface of secondary spherical particles to improve the interfacial *** 25℃,the NCM-KP electrode delivers a discharge specific capacity of 148.9 mAh·g^(-1) with a remarkable capacity retention ratio of 84.1% after 200 cycles at 1.0C and retains a high reversible specific capacity of 154.4 mAh·g^(-1) at *** at 1.0C and 60℃,it can maintain a reversible discharge specific capacity of 114.6 mAh·g^(-1) with 0.21% of capacity decay per cycle after 200 cycles,which is significantly lower than 0.40% for the pristine NCM ***,the charge transfer resistance of 238.89 Ω for the NCM-KP electrode is significantly lower than 947.41 Ω for the pristine NCM one by restricting the interfacial side ***,combining K+doping and Li_(3)PO_(4) coating is an effective strategy to enable the significant improvement of the electrochemical property of high-nickel cathode materials,which may be mainly attributed to the widened diffusion pathway and the formed Li_(3)PO_(4) protective layer,thus promoting Li~+diffusion rate and preventing the erosion of HF.

关键词： High-nickel cathode material Residual lithium K^(+)doping Li_(3)PO_(4)coating Lithium ions battery

A compact route for efficient production of high-purity β-Ga2O3 powder

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Rare Metals 2024年第9期43卷 4573-4584页

作者： xiao-Wei Zhou Gao-Jie Chen Liang Xu zhi-Jun Shao cheng Yang Yong-Pan Tian Zhuo Zhao School of Metallurgical Engineering Anhui University of Technology Low-Carbon Research Institute Anhui University of Technology

The present study has proposed a compact process for the production of high-purity β-Ga2O3powder by simply using gallium metal and water as the raw materials. The process basically consists of two essential steps including hydrothermal synthesis of Ga OOH and calcination of Ga OOH for the production of the target product of β-Ga2O3. Thermodynamic evaluation and systematic experiments were conducted for process parameter optimization. X-ray diffractometer（XRD）, scanning electron microscopy（SEM）, thermogravimetryDdifferential scanning calorimetry（TG-DSC） and X-ray photoelectron spectroscopy（XPS） were utilized to clarify the reaction mechanisms of the hydrothermal synthesis and transformation of Ga OOH to β-Ga2O3by calcination. Chemical analysis of the final product of β-Ga2O3obtained under the optimal conditions was carried out with inductively coupled plasma mass spectrometry（ICP-MS）, and the results showed that the contents of the representative impurities such as Ni, Cu, In, Mn, Co, Zn and Cr are obviously lower than the requirement of 5N β-Ga2O3standard, exhibiting excellent application prospect of the proposed process to produce high-purity β-Ga2O3.

关键词： Calcination Hydrothermal synthesis Purity Reaction mechanism β-Ga2O3

Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong zhi-cheng Zeng Guang-Zong Min Zhao-Hui Meng Guo-Qing Meng xiao-xiao Guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental Science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource ***,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus *** on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one ***,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk *** evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)***,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

Effect of stress-relief annealing on thermal fatigue cracks for die-casting die steels

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Journal of Iron and Steel Research International 2024年第5期31卷 1164-1176页

作者： zhi-xiong Bai xiao-chun Wu School of Materials Science and Engineering Shanghai UniversityShanghai200444China

The effect of stress-relief annealing at different stages of thermal fatigue tests on crack growth was investigated using a self-built thermal cycle *** results showed that annealing could limit crack expansion *** reduced dislocation density and released the accumulation of residual *** addition,the strain accumulation in carbides was reduced by this *** was also found that double annealing was even more effective at inhibiting crack expansion compared to single stress-relief *** 1000 cycles,the maximum crack length was reduced by 31.1%and 45.2%for the samples after using the optimal single and double annealing processes,*** single stress-relief annealing,earlier annealing provides more benefit in delaying crack ***,effective double stress-relief annealing requires a suitable time interval between the annealing ***,after 800 cycles,surface hardness decreased significantly accompanied by an increase in the size and number of carbides,and cracks expanded predominantly along grain boundaries.

关键词： Thermal fatigue Steel Carbide Stress-relief annealing Dislocation Residual stress

Clinical features and possible pathogenesis of multiple evanescent white dot syndrome with different retinal diseases and events:a narrative review

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 583-595页

作者： Chun-Li Chen Yi-Zhe cheng zhi-Han Zhang Ge Wang xiao-Yan Peng Department of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Beijing Ophthalmology and Visual Science Key Laboratory Beijing 100730China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510600Guangdong ProvinceChina

●Multiple evanescent white dot syndrome(MEWDS)is a rare fundus disease,characterized by acute vision loss and visual field *** previous studies have explained the possible pathogenesis and clinical features of primary ***,as the number of reported cases increases,secondary MEWDS occurs in other related retinal diseases and injuries,exhibiting some special *** associated retinal diseases include multifocal choroiditis/punctate inner choroidopathy(MFC/PIC),acute zonal occult outer retinopathy,best vitelliform macular dystrophy,pseudoxanthoma elasticum,and ocular *** related retinal injury is laser photocoagulation,surgery,and *** primary MEWDS often have a self-limiting course,secondary MEWDS may require treatment in some cases,according to the severity of concomitant diseases and ***,MEWDS secondary to MFC/PIC that is prone to forming choroidal neovascularization and focal choroidal excavation,needs positive treatment with *** possible underlying pathogenesis of secondary MEWDS is the exposure of choroidal antigen after the disruption of Bruch’s *** MEWDS-related features in secondary MEWDS are still evanescent under most *** prognosis and treatment depend on the severity of *** studies propose that the etiology is associated with immune factors,including viral infection,inflammation in choroid and Bruch’s membrane,and antigen exposure caused by retinal and/or choroidal *** pathogenic studies should be conducted in the *** diagnosis for secondary MEWDS could benefit patients in aspects of management and prognosis.

关键词： multiple evanescent white dot syndrome punctate inner choroidopathy multifocal choroiditis secondary multiple evanescent white dot syndrome

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo cheng Peng Zeng Chuan-zhi Zang Qing-Wei Dong Guang-Xi Wan xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Casual associations between blood metabolites and colon cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1995-2005页

作者： Ke-Yue Hu Yi-Quan cheng zhi-Long Shi Fu-Peng Ren Gang-Feng xiao Department of Hematology and Oncology Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina

BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal *** To investigate causal associations between blood metabolites and colon *** The study utilized a two-sample Mendelian randomization(MR)analysis to investigate the causal impact of 486 blood metabolites on colorectal *** primary method of analysis used was the inverse variance weighted *** further validate the results several sensitivity analyses were performed,including Cochran's Q test,MR-Egger intercept test,and MR robust adjusted profile *** additional analyses were conducted to ensure the reliability and robustness of the *** After rigorous selection for genetic variation,486 blood metabolites were included in the MR *** found Mannose[odds ratio(OR)=2.09(1.10-3.97),P=0.024],N-acetylglycine[OR=3.14(1.78-5.53),P=7.54×10^(-8)],X-11593-O-methylascorbate[OR=1.68(1.04-2.72),P=0.034],1-arachidonoylglycerophosphocholine[OR=4.23(2.51-7.12),P=6.35×10^(-8)]and 1-arachidonoylglycerophosphoethanolamine 4[OR=3.99(1.17-13.54),P=0.027]were positively causally associated with colorectal cancer,and we also found a negative causal relationship between Tyrosine[OR=0.08(0.01-0.63),P=0.014],Urate[OR=0.25(0.10-0.62),P=0.003],N-acetylglycine[0.73(0.54-0.98),P=0.033],X-12092[OR=0.89(0.81-0.99),P=0.028],Succinylcarnitine[OR=0.48(0.27-0.84),P=0.09]with colorectal cancer.A series of sensitivity analyses were performed to confirm the rigidity of the *** This study showed a causal relationship between 10 blood metabolites and colorectal cancer,of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk *** other five blood metabolites are protective factors.

关键词： Metabolites Colon cancer Mendelian randomization Genome-wide association studies Casual

Relationship between expression of CD44v6 and nm23-H1 and tumor invasion and metastasis in hepatocellular carcinoma

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World Journal of Gastroenterology 1998年第5期4卷 49-51页

作者： xiao cheng zhi, DAI Yi Min, YU Hong Yu, WANG Jian Jun and NI Can Rong

AIM To detect the expression of CD44v6 mRNA and nm23-H1 mRNA in hepatocellular carcinoma (HCC) by in situ hybridization, and to evaluate the relationship between their expression and also relationship between their expressions and tumor invasion and *** CD44v6 cDNA probe was synthesized with PCR technique and the nm23-H1 cRNA probe by in vitro transcription. The expression of CD44v6 mRNA and nm23-H1 mRNA was detected by in situ *** In group with high invasion and metastasis potential, the positive rates of CD44v6 mRNA and nm23-H1 mRNA were 80% (8/10) and 40% (4/10), in group with poor invasion and metastasis potential, they were 21.7% (5/23) and 91.3% (21/23). There was a positive correlation between the expression of CD44v6 mRNA and tumor invasion and metastasis potential in HCC (P＜0.01), and a reverse correlation between the expression of nm23-H1 mRNA and tumor invasion and metastasis potential (P＜0.01) and a reverse correlation in the expression between CD44v6 mRNA and nm23-H1 mRNA in HCC (P＜0.01).CONCLUSION Detection of CD44v6 mRNA and nm23-H1 mRNA may be useful for tumor invasion and metastasis in ***44 is a cell surface transmembrane glycoprotein. As a kind of adhesive molecule, it participates in cell-cell and cell-matrix adhesion and interactions. Many studies revealed a correlation between high-level expression of CD44, especially CD44v and tumor invasion, metastasis and prognosis. The exon 6v containing isoforms may be an independent diagnostic parameter[1,2]. Some other studies, however, had different results[3,4]. Some researches showed a reverse correlation between the expression of nm23-H1 mRNA and tumor metastasis[5,6]. In order to evaluate the relationship between the expression of CD44v6 mRNA and nm23-H1 mRNA and tumor invasive and metastatic potential in HCC and to evaluate the relationship in the expression between CD44v6 mRNA and nm23-H1 mRNA, we detected their expression in HCC by in situ hybridiza

关键词： liver neoplasms carcinoma, hepatocellular neoplasm invasion neoplasm metastasis CD44v6 nm23 H1 RNA, messenger