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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-liang Xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Remarkable average thermoelectric performance of the highly oriented Bi(Te,Se)-based thin films and devices

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Journal of Materiomics 2024年第2期10卷 366-376页

作者： zhiliang Li Xiaoqi Yang zhi Gao Jingxuan Wang Yuli xue Jianglong Wang Qian Cao zhihai Ding Shufang Wang Hebei Key Lab of Optic-Electronic Information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei ProvinceCollege of Physics Science and TechnologyHebei UniversityBaoding071002China Huabei Cooling Device Co. LtdXianghe065400China

Bi(Te,Se)-based compounds have attracted lots of attention for nearly two centuries as one of the most successful commercial thermoelectric(TE)materials due to their high performance at near room *** with 3D bulks,2D thin films are more compatible with modern semiconductor technology and have unique advantages in the construction of micro-and *** device applications,high average TE performance over the entire operating temperature range is ***,highly c-axis-oriented N-type Bi(Te,Se)epitaxial thin films have been successfully prepared using the pulsed laser deposition technology by adjusting the deposition *** film deposited at~260℃demonstrate a remarkable average power factor(PFave)of~24.4 mW·cm^(-1)·K^(-2)over the tem-perature range of 305e470 K,higher than most of the state-of-the-art Bi(Te,Se)-based ***,the estimated average zT value of the film is as high as~*** then constructed thin-film TE devices by using the above oriented Bi(Te,Se)films,and the maximum output power density of the device can reach up to~30.1 W/m^(2)under the temperature difference of 40 ***,the outstanding average TE performance of the highly oriented Bi(Te,Se)thin films will have an excellent panorama of applications in semiconductor cooling and power generation.

关键词： Bismuth telluride Oriented thin film Thermoelectric device Average power factor Output power density

Boost VS_(2) electrochemical reactive kinetics by regulating crystallographic planes and coupling carbon matrix for high performance sodium-ion storage

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Rare Metals 2024年第1期43卷 98-112页

作者： Min Zeng Ming-Shan Wang Lin Chen En-zhi Li Zhen-liang Yang Dan Zhou Hai-Jiao Xie Jun-Chen Chen zhi-Yuan Ma Bing-Shu Guo Bo Yu Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Energy Storage Research Institute Southwest Petroleum UniversityChengdu 610500China Institute of Materials China Academy of Engineering PhysicsMianyang 621908China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and TechnologyBeijingBeijing 100083China Hangzhou Yanqu Information Technology Co. Ltd.Hangzhou 310003China

Vanadium disulfide(VS_(2)) as a typical two-dimensional transition metal chalcogenide has excellent competitiveness for sodium-ion storage due to its wide layer spacing(0.575 nm),high theoretical capacity of 932mAh·g^(-1) originating from multi-electron electrochemical ***,continuous sodiation process accompanied by crystal structural evolution and collapse cause rapid capacity ***,novel few-layer VS_(2)nanosheets with open(001) crystal planes are in-situ constructed on reduced graphene oxide to solve these issues mentioned *** indicates that few-layer VS_(2)provides more Na^(+) storage activity due to the low Na^(+)surface migration energy barrier on exposed crystal(001)*** flexible and high electronic conductivity of carbon matrix also effectively builds multi-level buffer structure and electron transport kinetics to boost the Na^(+)insertion/conversion reactive activity on VS_(2) as well as Na^(+) pseudocapacitance storage kinetics on edges and defects of nano *** coupling effects result in high rate capability and long cycling stability as a battery/capacitor *** delivers conspicuous high energy density of 81 and 40 Wh·kg^(-1) at power density of 118 and 10,286W·kg^(-1),as well as 80% energy retention rate after 5000cycles,confirming its great application potential in sodiumbased storage devices.

关键词： Vanadium disulfide Reduced graphene oxide Anode Sodium-ion battery Sodium-ion capacitor

Risk stratification in gastric cancer lung metastasis: Utilizing an overall survival nomogram and comparing it with previous staging

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 357-381页

作者： zhi-Ren Chen Mei-Fang Yang zhi-Yuan Xie Pei-An Wang liang Zhang Ze-Hua Huang Yao Luo Department of Science and Education Xuzhou Medical UniversityXuzhou Clinical CollegeXuzhou 221000Jiangsu ProvinceChina Department of Neurology Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of Neurology Clinical LaboratoryGastrointestinal SurgeryCentral Hospital of XuzhouCentral Hospital of XuzhouXuzhou 221000Jiangsu ProvinceChina Department of Public Health Xuzhou Central HospitalXuzhou 221000Jiangsu ProvinceChina Department of Gastroenterology Xuzhou Centre HospitalXuzhou 221000Jiangsu ProvinceChina Department of Public Health Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Gastric cancer(GC)is prevalent and aggressive,especially when patients have distant lung metastases,which often places patients into advanced *** identifying prognostic variables for lung metastasis in GC patients,it may be po-ssible to construct a good prediction model for both overall survival(OS)and the cumulative incidence prediction(CIP)plot of the *** To investigate the predictors of GC with lung metastasis(GCLM)to produce nomograms for OS and generate CIP by using cancer-specific survival(CSS)*** Data from January 2000 to December 2020 involving 1652 patients with GCLM were obtained from the Surveillance,epidemiology,and end results program *** major observational endpoint was OS;hence,patients were se-parated into training and validation *** analysis determined va-rious *** and multivariate Cox analyses validated the independent predictive *** distinction and calibration were performed with the time-dependent area under the curve(AUC)and calibration *** evaluate the accuracy and clinical usefulness of the nomograms,decision curve analysis(DCA)was *** clinical utility of the novel prognostic model was compared to that of the 7th edition of the American Joint Committee on Cancer(AJCC)staging system by utilizing Net Reclassification Improvement(NRI)and Integrated Discrimination Improvement(IDI).Finally,the OS prognostic model and Cox-AJCC risk stratification model modified for the AJCC system were *** For the purpose of creating the OS nomogram,a CIP plot based on CSS was *** multivariate regression analysis identified eleven significant prognostic factors(P0),time-de-pendent ROC curve(training/v

关键词： Gastric cancer Lung metastasis Nomograms Surveillance Epidemiology Surveillance epidemiology and end results program database Overall survival Prognosis

Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

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Journal of Iron and Steel Research International 2024年第6期31卷 1355-1366页

作者： Sheng-hao Li Ao Huang Fan-bo Zeng Hui Peng Hao-ran Wei xue-chun Huang Sheng-qiang Song Hua-zhi Gu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory *** static magnetic field is a promising solution for improvement in the slag resistance of *** wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory *** slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy *** influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also *** contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory *** relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were *** provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

关键词： Alumina refractory ceramic Molten slag Weak magnetic field effect Reactive wetting Free radical

Identification of two compound heterozygous GNRHR mutations in two siblings with congenital hypogonadotropic hypogonadism

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Asian Journal of Andrology 2024年第1期26卷 120-122页

作者： Xiao-Bin Wang Ping Chen xue-Er Yu Zu-liang Yao Ting-Chao Guo Bo-Chen Pan Center for Reproductive Medicine Department of Obstetrics and GynecologyShengjing Hospital of China Medical UniversityShenyang 110004China NuProbe Shanghai 200433China Urology Surgery of The Affiliated Reproductive Hospital of China Medical University and Liaoning Key Laboratory of Reproductive Health Liaoning Research Institute of Family Planning(The Affiliated Reproductive Hospital of China Medical University)Shenyang 110031China NHC Key Laboratory of Reproductive Health and Medical Genetics China Medical UniversityShenyang 110122China

DearEditor,Congenital hypogonadotropic hypogonadism(CHH)is a rare genetic disease characterized by gonadotropin-releasing hormone(GnRH)deficiency or insufficiency and normal hypothalamic-pituitary structures,resulting in defective sexual maturation or/and infertility.!CHH presents as a variety of nonreproductive phenotypes,such as renal hypoplasia,dental hypoplasia,or oculomotor abnormalities.

关键词： pogon compound ism

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-zhi Lin Lu-Kun Feng Ya-Dong Li Chao-Fan Chang Cai-Zhen Zhu Ming-liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Bi^(3+)-activated dual-wavelength emitting phosphors toward effective optical thermometry

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Chinese Chemical Letters 2024年第3期35卷 486-492页

作者： Yu xue Yuqi Chen Guixian Li Weixi Xia Qinan Mao Lang Pei Meijiao Liu liang Chu Jiasong Zhong Center of Advanced Optoelectronic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310018China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China

Optical thermometry as an important local temperature-sensing technique,has received increasing attention in scientific and industrial ***,it is still a big challenge to develop luminescent materials with self-activated dual-wavelength emissions toward high-sensitivity optical ***,a novel ratiometric thermometric strategy of Bi^(3+)-activated dual-wavelength emission band was realized in the same lattice position with two local electronic states of La_(3)Sb_(1-x)Ta_xO_(7):Bi^(3+)(0≤x≤1.0)materials based on the different temperature-dependent emission behaviors,benefiting from the highlysensitive and regulable emission to the coordination environment of Bi^(3+).The structural and spectral results demonstrate that the emission tremendously shifted from green to blue with 68 nm and the intensity was enhanced 2.6 ***,the visual dual-wavelength emitting from two emission centers was presented by increasing the Ta^(5+)substitution concentration to 20%or 25%,mainly originating from the two local electronic states around the Bi^(3+)emission ***,the dual-wavelength with different thermal-quenching performance provided high-temperature sensitivity and good discrimination signals for optical thermometry in the range between 303 and 493 *** maximum relative sensitivity reached 2.64%/K(La_(3)Sb_(0.8)Ta_(0.2)O_(7):0.04Bi^(3+)@383 K)and 1.91%/K(La_(3)Sb_(0.75)Ta_(0.25)O_(7):0.04Bi^(3+)@388 K).This work reveals a rational design strategy of different local electronic states around the singledoping multiple emission centers towards practical applications,such as luminescence thermometry and white LED lighting.

关键词： Dual-wavelength emitting Cationic substitution Two local electronic states Optical thermometry Bi^(3+)-doped phosphor

Analysis of Electricity Consumption Pattern Clustering and Electricity Consumption Behavior

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Energy Engineering 2024年第9期121卷 2639-2653页

作者： liang Zhu Junyang Liu Chen Hu Yanli zhi Yupeng Liu Power Supply Service Management Center State Grid Jiangxi Electric Power Corporation LimitedNanchang330077China State Grid Jiangxi Electric Power Corporation Limited Nanchang330077China College of Electrical and Information Engineering Hunan UniversityChangsha410082China

Studying user electricity consumption behavior is crucial for understanding their power usage ***,the traditional clustering methods fail to identify emerging types of electricity consumption *** address this issue,this paper introduces a statistical analysis of clusters and evaluates the set of indicators for power usage *** fuzzy C-means clustering algorithm is then used to analyze 6 months of electricity consumption data in 2017 from energy storage equipment,agricultural drainage irrigation,port shore power,and electric ***,the proposed method is validated through experiments,where the Davies-Bouldin index and profile coefficient are calculated and *** showed that the optimal number of clusters is *** study demonstrates the potential of using a fuzzy C-means clustering algorithmin identifying emerging types of electricity consumption behavior,which can help power system operators and policymakers to make informed decisions and improve energy efficiency.

关键词： Electricity consumption clustering consumption behavior fuzzy C-means