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Hydrocracking diversity in n-dodecane isomerization on Pt/ZSM-22 and Pt/ZSM-23 catalysts and their catalytic performance for hydrodewaxing of lube base oil

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Petroleum Science 2020年第6期17卷 1752-1763页

作者： Shan-bin Gao Zhen Zhao Xue-Feng Lu Ke-bin Chi Ai-Jun Duan Yan-Feng Liu xiang-bin meng Ming-Wei Tan Hong-Yue Yu Yu-Ge Shen meng-Chen Li State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Petrochemical Research Institute PetroChina Company LimitedBeijing 100195China

Nobel metallic Pt/ZSM-22 and Pt/ZSM-23 catalysts were prepared for hydroisomerization of normal dodecane and hydrodewaxing of heavy waxy lube base *** hydroisomerization performance of n-dodecane indicated that the Pt/ZSM-23 catalyst preferred to crack the C-C bond near the middle of n-dodecane chain,while the Pt/ZSM-22 catalyst was favorable for breaking the carbon chain near the end of *** a result,more than 2%of light products(gas plus naphtha)and3%more of heavy lube base oil with low-pour point and high viscosity index were produced on Pt/ZSM-22 than those on Pt/ZSM-23 while using the heavy waxy vacuum distillate oil as feedstock.

关键词： Isomerization Hydrocracking Catalysts Pt/ZSM-22 Pt/ZSM-23 Dodecane Lube base oil

Uric acid is associated with cardiac death in patients with hypertrophic obstructive cardiomyopathy

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Journal of Geriatric Cardiology 2021年第4期18卷 281-288页

作者： Jun GAO Chun-Li SHAO xiang-bin meng Wen-Yao WANG Kuo ZHANG Jing-Jia WANG Ming-Qi ZHENG Yi-Da TANG Heart Center the First Hospital of Hebei Medical UniversityShijiazhuangChina Department of Cardiology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseaseChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Cardiology Fuwai Central China Cardiovascular HospitalCentral China Branch of National Center for Cardiovascular DiseasesZhengzhouChina Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationBeijing Key Laboratory of Cardiovascular Receptors ResearchBeijingChina

BACKGROUND The role of uric acid(UA) in survival of patients with hypertrophic obstructive cardiomyopathy(HOCM) has not been fully evaluated. This study aimed to determine whether UA could be an independent risk factor of cardiac death in patients with *** A total of 317 patients with HOCM, who were receiving conservative treatment in Fuwai Hospital from October2009 to December 2014, all of them completed UA evaluations, were analyzed. Patients were divided into three groups according to the UA levels: Tertile 1(≤ 318 μmol/L, n = 106), Tertile 2(319 to 397 μmol/L, n = 105), and Tertile 3(≥ 398 μmol/L, n = 106).RESULTS During a median follow-up of 45 months, 29 cardiac deaths(9.1%) occurred, including 6 sudden cardiac deaths and23 heart failure-related deaths. Cardiac death in Tertile 3(n = 16, 55.2%) was significantly higher than in Tertile 1(n = 6, 20.7%)and Tertile 2(n = 7, 24.1%). In univariate model, UA level(continuous value) showed predictive value of cardiac death [hazard ratio(HR) = 1.006, 95% CI: 1.003-1.009, P = 0.009]. Univariate Cox survival analysis had shown a significant higher property of cardiac death in patients of Tertile 3 when compared with those of Tertile 1, but cardiac death in patients of Tertile 2 did not show significant prognositic value compared with those of Tertile 1(HR = 3.927, 95% CI: 0.666-23.162, P = 0.131). UA was found to be an independent risk factor(HR = 1.005, 95% CI: 1.001-1.009, P = 0.009) of cardiac death in the multivariate regression analysis after the adjustment for age, body mass index, atrial fibrillation, hemoglobin, creatinine, high-sensitivity C-reactive protein, interventricular septum/left ventricular posterior wall ratio, left ventricular outflow tract and left ventricular ejection *** UA concentration was found to be independently associated with cardiac death in HOCM patients receiving conservative treatment. Randomized trials of UA-lowering agents for HOCM patients are warranted.

关键词： CRP Uric acid is associated with cardiac death in patients with hypertrophic obstructive cardiomyopathy

Assessment of causal direction between thyroid function and cardiometabolic health:a Mendelian randomization study

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Journal of Geriatric Cardiology 2022年第1期19卷 61-70页

作者： Jing-Jia WANG Zhen-Huang ZHUANG Can-Qing YU Wen-Yao WANG Wen-Xiu WANG Kuo ZHANG xiang-bin meng Jun GAO Jian TIAN Ji-Lin ZHENG Jie YANG Tao HUANG Chun-Li SHAO Yi-Da TANG Department of Cardiology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Epidemiology&Biostatistics School of Public HealthPeking UniversityBeijingChina Center for Intelligent Public Health Academy for Artificial IntelligencePeking UniversityBeijingChina Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalBeijingChina Key Laboratory of Molecular Cardiovascular Sciences(Peking University) Ministry of EducationBeijingChina

BACKGROUND Growing evidence have demonstrated that thyroid hormones have been involved in the processes of cardiovascular ***,the causal relationship of thyroid function and cardiometabolic health remains partly *** The Mendelian randomization(MR)was used to test genetic,potentially causal relationships between instrumental variables and cardiometabolic *** variants of free thyroxine(FT4)and thyrotropin(TSH)levels within the reference range were used as instrumental *** for genetic associations with cardiometabolic diseases were acquired from the genome-wide association studies of the FinnGen,CARDIoGRAM and CARDIoGRAMplusC4D,CHARGE,and *** study was conducted using summary statistic data from large,previously described *** between thyroid function and essential hypertension(EHTN),secondary hypertension(SHTN),hyperlipidemia(HPL),type 2 diabetes mellitus(T2DM),ischemic heart disease(IHD),myocardial infarction(MI),heart failure(HF),pulmonary heart disease(PHD),stroke,and non-rheumatic valve disease(NRVD)were *** Genetically predicted FT4 levels were associated with SHTN(odds ratio=0.48;95%CI=0.04−0.82,P=0.027),HPL(odds ratio=0.67;95%CI=0.18−0.88,P=0.023),T2DM(odds ratio=0.80;95%CI=0.42−0.86,P=0.005),IHD(odds ratio=0.85;95%CI=0.49−0.98,P=0.039),NRVD(odds ratio=0.75;95%CI=0.27−0.97,P=0.039).Additionally,genetically predicted TSH levels were associated with HF(odds ratio=0.82;95%CI=0.68−0.99,P=0.042),PHD(odds ratio=0.75;95%CI=0.32−0.82,P=0.006),stroke(odds ratio=0.95;95%CI=0.81−0.97,P=0.007).However,genetically predicted thyroid function traits were not associated with EHTN and *** Our study suggests FT4 and TSH are associated with cardiometabolic diseases,underscoring the importance of the pituitary-thyroid-cardiac axis in cardiometabolic health susceptibility.

关键词： cardio function random

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling Gong xiang-Li Zhong Hong-Jia Song Jin-bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Assessment of causal association between thyroid function and lipid metabolism:a Mendelian randomization study

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Chinese Medical Journal 2021年第9期134卷 1064-1069页

作者： Jing-Jia Wang Zhen-Huang Zhuang Chun-Li Shao Can-Qing Yu Wen-Yao Wang Kuo Zhang xiang-bin meng Jun Gao Jian Tian Ji-Lin Zheng Tao Huang Yi-Da Tang Department of Cardiology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Department of Epidemiology&Biostatistics School of Public HealthPeking UniversityBeijing 100191China Center for Intelligent Public Health Academy for Artificial IntelligencePeking UniversityBeijing 100191China Department of Cardiology Zhengzhou University People's HospitalCentral China Fuwai HospitalCentral China Branch of the National Cardiovascular CenterHenan Provincial People's HospitalZhengzhouHenan 450003China Department of Cardiology First Affiliated Hospital of Hebei Medical UniversityHebei 050031China Key Laboratory of Molecular Cardiovascular Sciences(Peking University) Ministry of EducationBeijing 100191China department of Cardiology Peking University Third HospitalBeijing 100191China

Background:Thyroid dysfunction is associated with cardiovascular ***,the role of thyroid function in lipid metabolism remains partly *** present study aimed to investigate the causal association between thyroid function and serum lipid metabolism via a genetic analysis termed Mendelian randomization(MR).Methods:The MR approach uses a genetic variant as the instrumental variable in epidemiological studies to mimic a randomized controlled trial.A two-sample MR was performed to assess the causal association,using summary statistics from the Atrial Fibrillation Genetics Consortium(n=537,409)and the Global Lipids Genetics Consortium(n=188,577).The clinical measures of thyroid function include thyrotropin(TSH),free triiodothyronine(FT3)and free thyroxine(FT4)levels,FT3:FT4 ratio and concentration of thyroid peroxidase antibodies(TPOAb).The serum lipid metabolism traits include total cholesterol(TC)and triglycerides,high-density lipoprotein,and low-density lipoprotein(LDL)*** MR estimate and MR inverse variance-weighted method were used to assess the association between thyroid function and serum lipid ***:The results demonstrated that increased TSH levels were significantly associated with higher TC(β=0.052,P=0.002)and LDL(β=0.041,P=0.018)*** addition,the FT3:FT4 ratio was significantly associated with TC(β=0.240,P=0.033)and LDL(β=0.025,P=0.027)***,no significant differences were observed between genetically predicted FT4 and TPOAb and serum ***:Taken together,the results of the present study suggest an association between thyroid function and serum lipid metabolism,highlighting the importance of the pituitary-thyroid-cardiac axis in dyslipidemia susceptibility.

关键词： Dyslipidemia Mendelian randomization Analysis Lipids Thyroid hormones

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin Fan Wen Zhigang Tao Hai Pu Tianci Deng Yaoyao meng Qingbin meng Hongwen Jing Bo meng Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： Song xiang Jinshui HUANG bingcheng WU School of Earth and Space Sciences University of Science and Technology of China CAS Center of Excellence in Comparative Planetary Studies

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress between different tectonic modes ***, the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number, but decreases between other tectonic modes. Furthermore, we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate, with the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa, which aligns with the strength of serpentinized mantle rock determined by experimental petrography. If the Archean mantle was 300°C warmer than it is today, then the Earth was in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei Liu Yantong Li meng-xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang Qinyi Guo bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability