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A Facile Solvothermal Synthesis of Monodisperse Ni Nanoparticles

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Chemical Research in Chinese Universities 2008年第3期24卷 260-262页

作者： YU peng-fei cui Bin ZHANG Yan SHI Qi-zhen Shaanxi Key Laboratory of Physico-lnorganic Chemistry Department of Chemistry Northwest University Xi ＇an 710069 P. R. China

A simple solvothermal approach was developed to synthesize uniform spherical monodisperse Ni nanoparticles, which can easily disperse in nonpolar solvents to form homogenous colloidal solution. The as-prepared sample was characterized by XRD, TEM, and FTIR. The results indicate that Ni nanoparticles have the structure of face-centered cube and a narrow distribution with a diameter of （3.5±0.5） nm. The FTIR spectrum reveals that the nanoparticles are coated with oleic acid. In the synthetic process, N2H4·H2O was used as a reducing agent and oleic acid as a surfactant. The probable formation mechanism of the spherical nanoparticles was also discussed.

关键词： Ni nanoparticle Solvothermal method Monodisperse

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Octanuclear Palladacycles with B(3)-H Bond Activation of o-Carborane

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Chinese Journal of Chemistry 2023年第3期41卷 307-313页

作者： Run-Ze Yuan peng-fei cui Yue-Jian Lin Guo-Xin Jin State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsDepartment of ChemistryFudan University2005 Songhu RoadShanghai200433 China

Herein,we describe the synthesis of a carborane-supported octanuclear palladacycle complex,Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(CH_(3)CN)_(4)(complex 1),with B(3)-H activations on o-carborane *** substitution reaction of 1 has been explored,and three of its substituted complexes Pd_(8)(o-C_(2)B_(10)H_(10)CS_(2)CH_(3))_(4)Cl_(4)(L)4(L=^(t)BuNC,2;L=C_(5)H_(5)N,3;L=C_(4)H_(8)S,4)have been *** m-and p-carborane disubstituted ligands m-and p-C_(2)B_(10)H_(10)(CS_(2)CH_(3))_(2)(ligands 5 and 6)as well as their B—H activated carborane complexes[m-C_(2)B_(10)H_(9)(CS_(2)CH_(3))_(2)PdCl](7)and[p-C_(2)B_(10)H_(8)(CS_(2)CH_(3))_(2)][PdCl(^(t)BuNC)]_(2)(8)have also been synthesized by the similar *** of these complexes have been characterized,including X-ray single crystal diffraction,NMR spectroscopy,IR spectroscopy and elemental analysis methods.

关键词： Carborane Palladacycle Regioselective B-H activation Polynuclear complex Dithioester chemistry

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan cui peng Chen peng‑fei Wang Xiao‑Wu Li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

Prognostic factors for overall survival in prostate cancer patients with different site-specific visceral metastases: A study of 1358patients

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World Journal of Clinical Cases 2020年第1期8卷 54-67页

作者： peng-fei cui Xiao-Feng Cong Feng Gao Jia-Xin Yin Zi-Ru Niu Song-Chen Zhao Zi-Ling Liu Cancer Center the First Hospital of Jilin University

BACKGROUND Distant metastasis,particularly visceral metastasis(VM),represents an important negative prognostic factor for prostate cancer(PCa)***,due to the lower rate of occurrence of VM,studies on these patients are relatively ***,studies focusing on prognostic factors associated with PCa patients with VM are highly *** To investigate the prognostic factors for overall survival(OS)in PCa patients with lung,brain,and liver metastases,respectively,and evaluate the impact of site-specific and number-specific VM on *** Data on PCa patients with VM were extracted from the Surveillance,Epidemiology,and End Results database between 2010 and *** and multivariate Cox regression analyses were used to analyze the association between clinicopathological characteristics and survival of patients with different site-specific ***-Meier analyses and Log-rank tests were performed to analyze the differences among the *** A total of 1358 PCa patients with site-specific VM were identified from 2010 to *** age(>70 years)(P8)(P70 years)(P=0.010)and higher Gleason score(>8)(P=0.001)were associated with shorter OS in PCa patients with liver *** patients with isolated lung metastases exhibited significantly better survival outcomes compared with PCa patients with other single sites of VM(P<0.001).PCa patients with a single site of VM exhibited a superior OS compared with PCa patients with multiple sites of VM(P<0.001).CONCLUSION This is the first Surveillance,Epidemiology,and End Results-based study to determine prognostic factors affecting OS in PCa patients with different si

关键词： Prognostic factors Overall survival Prostate cancer Visceral metastases

CONCENTRATION AND VELOCITY OF DEBRIS FLOWS

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International Journal of Sediment Research 2002年第3期17卷 233-243页

作者： Xiangjun fei,peng cui,Yong LI Tsinghua University Beijing 100084 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences & Ministry of Water Conservancy Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences & Mini

Debris flows in nature generally fall into three groups distinct in their grain composition: water-stone flow, or sub-viscous debris flow, dominated by coarse grains; muddy flow, dominated by fine grains; and viscous debris flow composed of grains in large range. Liquid-phase velocity and sedimentary delivery resistance of sub-viscous debris flow have been discussed based on the composition characters of sub- and high-viscous debris flows. It is revealed that the presence of fine grains plays a vital role in affecting resistance and average velocity, particularly when the volume fraction of grains in the flow is relatively high, i.e. Sv > 0.45. Grain-size distribution of viscous debris flow is characterized by a bimodal curve, which explains the properties like high density and low resistance gradient of debris flows. A calculation formula is finally put forward, which has to some extent overcome locality limits and achieved a good agreement with the field observations of debris flows in Southwest China.

关键词： Sub-viscous debris flow Viscous debris flow Grain composition Concentration Velocity

A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng Hao-Yu Pan Hai-Ge Wang Shou-Kun Xu Xiao-peng Yan Chao-Wei Li Ming-Guo peng Hao-Ping peng Lin Shi Meng cui fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

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Changes of coastline and tidal flat and its implication for ecological protection under human activities: Take China’s Bohai Bay as an example

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China Geology 2024年第1期7卷 26-35页

作者： Yong Li Ming-zheng Wen Heng Yu peng Yang fei-cui Wang Fu Wang Tianjin Center China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Key Laboratory of Coast Geo-environment China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Tianjin Key Laboratory of Coast Geological Processes and Environmental Safety Tianjin 300170China Hebei University of Environmental Engineering Qinhuangdao 066102China Hebei Engineering Research Center for Ecological Restoration of seaward Rivers and Coastal Waters Qinhuangdao 066102China Department of Earth and Environment Boston UniversityBoston 02215USA

The change processes and trends of shoreline and tidal flat forced by human activities are essential issues for the sustainability of coastal area,which is also of great significance for understanding coastal ecological environment changes and even global *** on field measurements,combined with Linear Regression(LR)model and Inverse Distance Weighing(IDW)method,this paper presents detailed analysis on the change history and trend of the shoreline and tidal flat in Bohai *** shoreline faces a high erosion chance under the action of natural factors,while the tidal flat faces a different erosion and deposition patterns in Bohai Bay due to the impact of human *** implication of change rule for ecological protection and recovery is also *** should be taken to protect the coastal ecological *** models used in this paper show a high correlation coefficient between observed and modeling data,which means that this method can be used to predict the changing trend of shoreline and tidal *** research results of present study can provide scientific supports for future coastal protection and management.

关键词： Shoreline Tidal flat Erosion deposition patterns Changing trend Ecological protection Human activity Linear regression model Inverse distance weighing method Prediction Bohai Bay

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Selection of dialysis methods for end-stage kidney disease patients with diabetes

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World Journal of Diabetes 2024年第9期15卷 1862-1873页

作者： Yao-Hua Hu Ya-Li Liu Ling-fei Meng Yi-Xian Zhang Wen-peng cui Department of Nephrology The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina

The increasing prevalence of diabetes has led to a growing population of endstage kidney disease(ESKD)patients with ***,kidney transplantation is the best treatment option for ESKD patients;however,it is limited by the lack of ***,dialysis has become the standard treatment for ESKD ***,the optimal dialysis method for diabetic ESKD patients remains *** patients with diabetes often present with complex conditions and numerous ***,these patients face a high risk of infection and technical failure,are more susceptible to malnutrition,have difficulty establishing vascular access,and experience more frequent blood sugar fluctuations than the general ***,this article reviews nine critical aspects:Survival rate,glucose metabolism disorder,infectious complications,cardiovascular events,residual renal function,quality of life,economic benefits,malnutrition,and volume *** study aims to assist clinicians in selecting individualized treatment methods by comparing the advantages and disadvantages of hemodialysis and peritoneal dialysis,thereby improving patients’quality of life and survival rates.

关键词： Diabetes End-stage kidney disease Hemodialysis Peritoneal dialysis Dialysis methods selection

Heterostructural NiFeW disulfide and hydroxide dual‐trimetallic core‐shell nanosheets for synergistically effective water oxidatio

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Carbon Energy 2024年第8期6卷 192-204页

作者： peng‐fei Guo Yang Yang Bing Zhu Qian‐Nan Yang Yan Jia Wei‐Tao Wang Zhao‐Tie Liu Shi‐Qiang Zhao Xun cui Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi'anChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'anChina Key Laboratory of Carbon Materials of Zhejiang Province Wenzhou Key Lab of Advanced Energy Storage and ConversionZhejiang Province Key Lab of Leather EngineeringCollege of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhanChina

A stable and highly active core‐shell heterostructure electrocatalyst is essential for catalyzing oxygen evolution reaction(OER).Here,a dual‐trimetallic core‐shell heterostructure OER electrocatalyst that consists of a NiFeWS_(2)inner core and an amorphous NiFeW(OH)_(z)outer shell is designed and synthesized using in situ electrochemical *** electrochemical measurements of different as‐synthesized catalysts with a similar mass loading suggest that the core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)nanosheets exhibit the highest overall performance compared with that of other bimetallic reference catalysts for the ***,the nanosheet arrays were in situ grown on hydrophilic‐treated carbon paper to fabricate an integrated three‐dimensional electrode that affords a current density of 10 mA cm^(−2)at a small overpotential of 182 mV and a low Tafel slope of 35 mV decade^(−1)in basic *** Faradaic efficiency of core‐shell Ni_(0.66)Fe_(0.17)W_(0.17)S_(2)@amorphous NiFeW(OH)_(z)is as high as 99.5%for *** scanning electron microscope,transmission electron microscope,and X‐ray photoelectron spectroscopy analyses confirm that this electrode has excellent stability in morphology and elementary composition after long‐term electrochemical ***,density functional theory calculations further indicate that the core‐shell heterojunction increased the conductivity of the catalyst,optimized the adsorption energy of the OER intermediates,and improved the OER *** study provides a universal strategy for designing more active core‐shell structure electrocatalysts based on the rule of coordinated regulation between electronic transport and active sites.

关键词： amorphous NiFeW hydroxide core‐shell heterojunction in situ electrochemical tuning NiFeW disulfide oxygen evolution reaction