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Modeling analysis of cobalt-based Fischer-Tropsch catalyst particles

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Chinese Journal of Chemical Engineering 2024年第6期70卷 82-92页

作者： Huashuai Wu Gang Wang yong yang yongwang Li College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China National Energy Research&Development Center for Coal to Liquid Fuels Synfuels China CompanyLimitedBeijing 101400China

The influences of particle size,shape,and catalyst distribution on the reactivity and hydrocarbon product selectivity of a cobalt-based catalyst for Fischer-Tropsch synthesis were investigated in the present work.A self-consistent kinetic model for Fischer-Tropsch reaction proposed here was found to correlate experimental data well and hence was used to describe the consumption rates of reactants and formation rates of hydrocarbon *** perturbed-chain statistical associating fluid theory equation of state was used to describe vapor-liquid equilibrium behavior associated with Fischer-Tropsch *** interaction between intraparticle diffusion and Fischer-Tropsch reaction was investigated in *** showed that in order to avoid the adverse influence of intraparticle diffusional limitations on catalyst reactivity and product selectivity,the use of small particles is *** eggshell spherical particles are shown to keep the original catalyst reactivity and enhance the selectivity of heavy hydrocarbon *** suitable layer thickness for a spherical particle with a diameter of 2 mm is nearly 0.15 *** the same outer diameter of 2 mm,the catalyst reactivity and heavy product selectivity of hollow cylindrical particles with a layer thickness of 0.25 mm are found to be larger than eggshell spherical *** the viewpoint of catalytic performance,hollow cylindrical particles are a better choice for industrial applications.

关键词： Fischer-Tropsch synthesis Kinetic modeling Vapor-liquid equilibria Numerical simulation Intraparticle diffusion Particle shapes

Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions

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Plant Diversity 2024年第2期46卷 265-273页

作者： Ju Li Shu-bin Zhang yang-Ping Li CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina University of Chinese Academy of Sciences Beijing 100049China

To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native ***,few studies have compared the photosynthetic dynamics between invasive and native species during light *** compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady *** photosynthetic dynamics and leaf traits differed among *** showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun ***,the slow induction response may be attributed to the longer stomatal length in *** had a significant effect on photosynthetic dynamics in *** and *** but not in *** shady habitat,*** had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in *** than in the two native *** contrast,*** had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic ***,in both habitats,*** had an overall higher carbon gain during light fluctuations than the two native *** results indicated that *** can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.

关键词： Invasive plant Photosynthetic induction Photosynthetic relaxation Carbon gain Stomatal traits Tithonia diversifolia

Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

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China Communications 2024年第6期21卷 23-39页

作者： Jiang Jie Lyu bin Chen Pengcheng yang Zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

Effect of Menopausal Hormone Replacement Therapy on Cytokine Patterns in a Perimenopausal Mouse Model Established by the Ovarian Castration Method

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Chinese Journal of Biomedical Engineering(English Edition) 2024年第1期33卷 40-48页

作者： HE bin-bin ZHANG Ju-shun WANG Jin-yong Longyan First Affiliated Hospital of Fujian Medical University Longyan Fujian 364000China

Objective: To investigate the effect of perimenopausal hormone replacement therapy(HRT) on cytokine patterns in a perimenopausal mouse model established by ovarian castration. Methods: The mice were divided into natural menopause group,ovariectomy group and HRT group, with 15 mice in each group, and the estrous cycle, estrous frequency and menopausal time of the mice were determined by vaginal cytology,and the estrous cycle, estrous frequency and menopausal time were compared among the three groups. The serum levels of estradiol(E2) and progesterone(P4) in each group were detected by double-antibody sandwich ELISA, and the levels of interferon gamma(IFN-γ), interleukin-2(IL-2), IL-4 and IL-10 in the spleen γ tissues of mice were detected by ELISA. Results: The time of menopause(53.07±3.99) d in the HRT group was between that of the natural menopause group(80.80±3.26) d and that of the ovariectomy group(16.27±4.35) d, with a statistically significant difference in the two-by-two comparison of the three groups(P<0.05). The levels of serum E2(694.4±128.3) ng/L and P4(14.2 ±6.0) ng/L in the HRT therapy group are between those of the ovariectomy group and the natural menopause group, with statistically significant differences between the groups(P<0.05). The levels of IL-2(30.9±5.3) pg/ml, IL-4(9.4±1.6) pg/ml, IL-10(19.7±3.1) pg/ml, IFN-γ(22.0±3.7) pg/ml in the HRT group were all between those of natural menopause group and ovariectomy group. The Th1/Th2 ratio in the ovariectomy group was 7.55±1.57, higher than that in the natural menopause group(1.53±0.48) and HRT group(2.38 ±0.44), with statistically significant differences(P<0.05). Conclusion:Menopausal HRT can partially correct the imbalance of Th1/Th2 cytokines, which is able to provide an experimental basis for the regulation of menopause-related immune imbalance by HRT.

关键词： menopause hormone replacement therapy(HRT) ovariectomy mouse model cytokine pattern

Diagnostic performance of intravascular ultrasound-based fractional flow reserve in evaluating of intermediate left main stenosis

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Journal of Geriatric Cardiology 2024年第1期21卷 34-43页

作者： yong-Gang SUI Cheng yang Chang-Dong GUAN Yan-Lu XU Na-Qiong WU Wei-Xian yang yong-Jian WU Ke-Fei DOU Yue-Jin yang Shu-bin QIAO Wei YU Bo XU Sheng-Xian TU Jie QIAN Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Catheterization Laboratories Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Biomedical Instrument Institute School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina National Clinical Research Center for Cardiovascular Diseases BeijingChina

BACKGROUND The recently introduced ultrasonic flow ratio(UFR),is a novel fast computational method to derive fractional flow reserve(FFR)from intravascular ultrasound(IVUS)*** the present study,we evaluate the diagnostic performance of UFR in patients with intermediate left main(LM)*** This is a prospective,single center study enrolling consecutive patients with presence of intermediated LM lesions(diameter stenosis of 30%-80%by visual estimation)underwent IVUS and FFR *** independent core laboratory assessed offline UFR and IVUS-derived minimal lumen area(MLA)in a blinded *** Both UFR and FFR were successfully achieved in 41 LM patients(mean age,62.0±9.9 years,46.3%diabetes).An acceptable correlation between UFR and FFR was identified(r=0.688,P50%(AUC=0.66,P<0.001)and numerically higher than IVUS-derived MLA(AUC=0.82;P=0.09).Patient level diagnostic accuracy,sensitivity and specificity for UFR to identify FFR≤0.80 was 82.9%(95%CI:70.2-95.7),93.1%(95%CI:82.2-100.0),58.3%(95%CI:26.3-90.4),*** In patients with intermediate LM diseases,UFR was proved to be associated with acceptable correlation and high accuracy with pressure wire-based FFR as standard *** present study supports the use of UFR for functional evaluation of intermediate LM stenosis.

关键词： stenosis flow fractional

Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism

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Chinese Physics Letters 2024年第8期41卷 58-68页

作者： yangwu Tong yong yang Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations,with focus on the effects of quantum *** low temperatures,quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and *** the case of dimer desorption,two types of mechanisms,namely the traditional one-step desorption in the form of molecules(molecular mechanism),and the two-step desorption in the form of individual atoms(atomic mechanism),are studied and *** the ortho-dimers,the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature,which is∼300K and 200K for H and D,respectively.

关键词： desorption quantum mechanism

Special Unipotent Representations of Simple Linear Lie Groups of Type A

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Acta Mathematica Sinica,English Series 2024年第3期40卷 707-716页

作者： Dan BARBASCH Jia Jun MA bin yong SUN Chen Bo ZHU Department of Mathematics Cornell UniversityIthacaNY 14853USA School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China Department of Mathematics Xiamen University Malaysia CampusSepangSelangor Darul Ehsan43900Malaysia Institute for Advanced Study in Mathematics&New Cornerstone Science Laboratory Zhejiang UniversityHangzhou 310058P.R.China Department of Mathematics National University of Singapore10 Lower Kent Ridge RoadSingapore 119076

Let G be a special linear group over the real,the complex or the quaternion,or a special unitary *** this note,we determine all special unipotent representations of G in the sense of Arthur and Barbasch-Vogan,and show... 详细信息

关键词： Special unipotent representations unitary representations coherent continuation Weyl group representations

2D Ca/Nb-based perovskite oxide with Ta doping as highly efficient H_(2)O_(2)synthesis catalyst

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Nano Research 2024年第6期17卷 4934-4942页

作者： Xingchen yang yang Gao Xiaohui Xu Wenqiang Xu Denghui Wang bin Luo Dong Liu Tao Liang bin Wang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnologythe University of QueenslandSt LuciaQLD 4072Australia State Key Laboratory of Organic–Inorganic Composites College of Chemical EngineeringCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China State Key Lab of Silicon Materials Zhejiang UniversityHangzhou 310027China

Perovskite oxides(POs)are emerging as a class of highly efficient catalysts for reducing oxygen to H_(2)*** a rich variety of POs-based catalysts have been developed by tuning the complex composition,a highly efficient PO catalyst that is able to alter the reaction pathway from a 4e−process to a 2e−process for H_(2)O_(2)production has rarely been *** modified the structure and composition of a Ca-and Nb-based PO material by realizing a uniform two-dimensional(2D)morphology and varied Ta doping,resulting in the 2D Ca_(2)Nb_(3−x)Ta_(x)O_(10)−(x=0,0.5,1,and 1.5)monolayer *** obtained catalysts exhibit a dominant 2e−pathway and show exceptional H_(2)O_(2)production *** typical Ca_(2)Nb_(2.5)Ta_(0.5)O_(10)−nanoflakes showed an onset potential of 0.735 V *** hydrogen electrode(RHE),a remarkably high selectivity over 95%across a wide range of 0.3-0.7 V,an impressively high Faradaic efficiency of 94%,and a notable H_(2)O_(2)productivity of 1571 mmol·gcat^(−1)·h^(−1).These findings highlight the great potential of 2D perovskite oxide nanoflakes as advanced electrocatalysts for 2e−oxygen reduction reaction.

关键词： perovskite oxide H_(2)O_(2) two-electron oxygen reduction reaction catalyst Ca_(2)Nb_(3-x)Ta_(x)O_(10)-nanoflakes

Cell fate regulation governed by p53: Friends or reversible foes in cancer therapy

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Cancer Communications 2024年第3期44卷 297-360页

作者： bin Song Ping yang Shuyu Zhang Laboratory of Radiation Medicine West China Second University HospitalSichuan UniversityChengduSichuanP.R.China The Second Affiliated Hospital of Chengdu Medical College China National Nuclear Corporation 416 HospitalChengduSichuanP.R.China Laboratory of Radiation Medicine NHC Key Laboratory of Nuclear Technology Medical TransformationWest China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengduSichuanP.R.China

Cancer is a leading cause of death *** therapies aimed at key oncogenic driver mutations in combination with chemotherapy and radiother-apy as well as immunotherapy have benefited cancer patients *** protein p53(TP53),a crucial tumor suppressor gene encoding p53,reg-ulates numerous downstream genes and cellular phenotypes in response to various *** affected genes are involved in diverse processes,includ-ing cell cycle arrest,DNA repair,cellular senescence,metabolic homeostasis,apoptosis,and ***,accumulating recent studies have contin-ued to reveal novel and unexpected functions of p53 in governing the fate of tumors,for example,functions in ferroptosis,immunity,the tumor microenvi-ronment and microbiome *** the possibilities,the evolutionary plasticity of p53 is the most controversial,partially due to the dizzying array of biological functions that have been attributed to different regulatory mechanisms of p53 *** 40 years after its discovery,this key tumor suppressor remains somewhat *** intricate and diverse functions of p53 in reg-ulating cell fate during cancer treatment are only the tip of the iceberg with respect to its equally complicated structural biology,which has been painstak-ingly ***,TP53 mutation is one of the most significant genetic alterations in cancer,contributing to rapid cancer cell growth and tumor ***,we summarized recent advances that implicate altered p53 in modulating the response to various cancer therapies,including chemotherapy,radiotherapy,and ***,we also discussed potential strategies for targeting p53 as a therapeutic option for cancer.

关键词： cancer chemotherapy drug targeting immunotherapy p53 tumor suppressor