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An Online Algorithm Based on Replication for Using Spot Instances in IaaS Clouds

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Journal of Computer Science & Technology 2024年第1期39卷 103-115页

作者：许志伟潘丽刘士军 School of Software Shandong UniversityJinan 250101China

Infrastructure-as-a-Service(IaaS)cloud platforms offer resources with diverse buying *** can run an instance on the on-demand market which is stable but expensive or on the spot market with a significant ***,users have to carefully weigh the low cost of spot instances against their poor *** instances will be revoked when the revocation event ***,an important problem that an IaaS user faces now is how to use spot in-stances in a cost-effective and low-risk *** on the replication-based fault tolerance mechanism,we propose an on-line termination algorithm that optimizes the cost of using spot instances while ensuring operational *** prove that in most cases,the cost of our proposed online algorithm will not exceed twice the minimum cost of the optimal of-fline algorithm that knows the exact future a *** a large number of experiments,we verify that our algorithm in most cases has a competitive ratio of no more than 2,and in other cases it can also reach the guaranteed competitive ratio.

关键词： Infrastructure-as-a-Service(IaaS)cloud cost management competitive analysis online algorithm spot instance

Active sites and reaction mechanisms of COhydrogenation on zinc-based mixed oxide catalysts

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Science China Chemistry 2024年

作者： Zhuo-Yan Yao Si-Cong Ma zhi-pan Liu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Key Laboratory of Computational Physical ScienceDepartment of Chemistry Fudan University State Key Laboratory of Metal Organic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai Qi zhi Institution

The conversion of C1 molecules, COx（CO and CO2）, to valuable chemical products has garnered ever-increasing *** many routes, the hydrogenation via thermal catalysis is particularly promising as a key clean energy technology with the increasing supply of green H2. Zinc-based mixed oxide catalysts exhibit exceptional catalytic performance in the COxhydrogenation to value-added hydrocarbons, especially in combination with zeolite. This review overviews the recent achievements in understanding the active sites and reaction mechanisms of COxhydrogenation on zinc-based mixed oxide catalysts, focusing on three most-studied zinc-based mixed oxide catalysts, namely ZnCrOx, ZnAlOxand ZnZrOx. The challenges and future directions are also discussed.

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Analytical Solutions for an Isotropic Elastic Half-Plane with Complete Surface Effects Subjected to a Concentrated/Uniform Surface Load

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Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： Xia-Hui pan School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane subjected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,combined effects of surface elasticity and residual surface stress should be *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti problems with surface *** solutions presented in this work may be helpful for understanding the contact behaviors between solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions

A semi-analytical pressure and rate transient analysis model for inner boundary and propped fractures exhibiting dynamic behavior under long-term production conditions

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Petroleum Science 2024年第4期21卷 2520-2535页

作者： Lin-Song Cheng Chong Cao Quan-Yu pan Pin Jia Ren-Yi Cao zhi-Kai Wang Jun-Jie Shi College of Petroleum Engineering China University of Petroleum (Beijing) Sinopec Petroleum Exploration and Production Research Institute CNOOC Research Institute State Key Laboratory of Water Resources Protection and Utilization in Coal Mining

The loss of hydrocarbon production caused by the dynamic behavior of the inner boundary and propped fractures under long-term production conditions has been widely reported in recent studies. However,the quantitative relationships for the variations of the inner boundary and propped fractures have not been determined and incorporated in the semi-analytical models for the pressure and rate transient analysis. This work focuses on describing the variations of the inner boundary and propped fractures and capturing the typical characteristics from the pressure transient curves.A generalized semi-analytical model was developed to characterize the dynamic behavior of the inner boundary and propped fractures under long-term production conditions. The pressure-dependent length shrinkage coefficients, which quantify the length changes of the inner zone and propped fractures, are modified and incorporated into this multi-zone semi-analytical model. With simultaneous numerical iterations and numerical inversions in Laplace and real-time space, the transient solutions to pressure and rate behavior are determined in just a few seconds. The dynamic behavior of the inner boundary and propped fractures on transient pressure curves is divided into five periods: fracture bilinear flow(FR1),dynamic PFs flow(FR2), inner-area linear flow(FR3), dynamic inner boundary flow(FR4), and outer-area dominated linear flow(FR5). The early hump during FR2 period and a positive upward shift during FR4period are captured on the log-log pressure transient curves, reflecting the dynamic behavior of the inner boundary and propped fractures during the long-term production *** transient pressure behavior will exhibit greater positive upward trend and the flow rate will be lower with the shrinkage of the inner boundary. The pressure derivative curve will be upward earlier as the inner boundary shrinks more rapidly. The lower permeability caused by the closure of un-propped fractures in the inner zo

关键词： Semi-analytical model Length shrinkage Dynamic behavior Boundary changes Transient behavior

A triboelectric nanogenerator based on a spiral rotating shaft for efficient marine energy harvesting of the hydrostatic pressure differential

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Materials Reports(Energy) 2024年第3期4卷 69-76页

作者： Xuemei Song Yuan chao pan Chang Bao Han Chang Xin Liu Yaxiaer Yalikun Hui Yan Yang Yang Key Laboratory of Advanced Functional Materials(Beijing University of Technology) Ministry of EducationBeijing Key Lab of Microstructure and Property of Advanced MaterialsBeijing University of TechnologyBeijing100124PR China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya572000PR China Division of Materials Science Nara Institute of Science and Technology8916-5 Takayama-choIkomaNara630-0192Japan

Equipment used in underwater sensing and exploration typically relies on cables or batteries for energy supply,resulting in a limited and inconvenient energy supply and marine environmental pollution that hinder the sustainable development of distributed ocean sensing ***,we design a deep-sea differential-pressure triboelectric nanogenerator(DP-TENG)based on a spiral shaft drive using modified polymer materials to harness the hydrostatic pressure gradient energy at varying ocean depths to power underwater *** spiral shaft structure converts a single compression into multiple rotations of the TENG rotor,achieving efficient conversion of differential pressure *** multi-pair electrode design enables the DP-TENG to generate a peak current of 61.7μA,the instantaneous current density can reach 0.69μA cm^(-2),and the output performance can be improved by optimizing the spiral angle of the *** DP-TENG can charge a 33μF capacitor to 17.5 V within five working *** can also power a digital calculator and light up 116 commercial power light-emitting diodes,demonstrating excellent output *** its simple structure,low production cost,and small form factor,the DP-TENG can be seamlessly integrated with underwater *** results hold broad prospects for underwater blue energy harvesting and are expected to contribute to the development of self-powered equipment toward emerging“smart ocean”and blue economy applications.

关键词： Triboelectric nanogenerators Blue energy Energy harvesting Differential pressure energy Self-power sensor

Activatable fluorescent probes for imaging and diagnosis of rheumatoid arthritis

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Military Medical Research 2024年第2期11卷 287-307页

作者： pan Luo Fu-Qiang Gao Wei Sun Jun-You Li Cheng Wang Qing-Yu Zhang zhi-Zhuo Li Peng Xu Department of Joint Surgery Honghui HospitalXi'an Jiaotong UniversityXi'an 710054China Department of Orthopedics China-Japan Friendship HospitalBeijing 100029China Department of Orthopaedic Surgery of the Perelman School of Medicine University of PennsylvaniaPhiladelphiaPA 19104USA School of Mechanical Engineering Sungkyunkwan UniversitySuwon 16419South Korea Department of Orthopaedic Surgery Peking University Third HospitalPeking UniversityBeijing 100191China Department of Orthopedics Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China State Key Laboratory of Pharmaceutical Biotechnology Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Rheumatoid arthritis(RA)is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability,thus adversely affecting locomotion ability and life ***,good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of *** fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo ***,we review the fluorescent probes developed for the detection and imaging of RA biomarkers,namely reactive oxygen/nitrogen species(hypochlorous acid,peroxynitrite,hydroxyl radical,nitroxyl),pH,and cysteine,and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.

关键词： Rheumatoid arthritis Fluorescent probe Imaging Diagnosis Biomarker

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Recovering noble metals from waste streams using porous organic frameworks for heterogeneous catalysis

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Science China Chemistry 2024年

作者： Yu pan Michelle ?hlén Maria Str?mme chao Xu Division of Nanotechnology and Functional Materials Department of Materials Science and Engineering ?ngstr?m LaboratoryUppsala University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Recovering noble metals from waste resources and incorporating them into catalysts stands out as a promising strategy for advancing sustainability within the catalysis field. This review provides a comprehensive overview of recent investigations into noble metal recovery from waste streams, specifically employing porous organic frameworks(POFs). Additionally, the study delves into the utilization of the resultant composites, enriched with noble metals, in heterogeneous catalysis. Moreover, we offer insights into the challenges faced and outline prospects for the practical implementation of extracting noble metal catalysts from waste streams using POFs, aiming to develop cost-effective, sustainable, and efficient heterogeneous catalysts.

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Investigation on the mechanism of Qiangxinhuoli prescription in the treatment of chronic heart failure based on p38-MAPK signaling pathway

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Traditional Medicine Research 2024年第7期9卷 13-24页

作者： Di Guo Qiu-Han Zheng Di Wang zhi pan Xiao-Ling Shang College of Basic Medicine Changchun University of Chinese MedicineChangchun 130117China. Jilin Ginseng Academy Changchun University of Chinese MedicineChangchun 130117China.

Background:The aim of this study is to investigate the mechanism of action underlying the therapeutic effects of the national patent Chinese medicine compound“Qiangxinhuoli prescription(QXHLF)”on chronic heart failure(CHF).Methods:In vitro,the H_(9)C_(2) cell model was induced by ANGII,and cell proliferation and related protein expression were detected by Cell Counting Kit-8 and Western *** vivo,A rat model of CHF was prepared by ligation of the left anterior descending coronary *** effects of QXHLF on cardiac function in CHF rats were evaluated by cardiac index,hemodynamic changes,enzyme-linked immunosorbent assay,hematoxylin-eosin staining,immunohistochemistry,Western blot and *** expression of pro-apoptotic factors and anti-apoptotic factors,as well as TGFβ1,p-p38,TAK 1 mRNA,and protein,were ***:In vitro,QXHLF has a significant inhibitory effect on the proliferation of H_(9)C_(2) *** can reduce the expression levels of TAK 1,TGFβ1,p-p38,Caspase3 and BAX proteins in H_(9)C_(2) cells,and increase the expression level of BCL_(2) *** vivo,QXHLF has the potential to increase left ventricular systolic pressure,m aximum rate of change in left ventricular pressure while decreasing left ventricular end diastolic pressure,and inhibiting the serum levels of brain natriuretic ***,QXHLF exhibits significant improvements in the pathological alterations of myocardial cells and fibers in CHF rats,leading to enhanced myocardial tissue morphology and notable advantages in combating myocardial *** can reduce the levels of BAX and Caspase3 and up-regulate the expression of BCL_(2),thereby inhibiting cardiomyocyte ***,QXHLF demonstrates inhibitory effects on the mRNA and protein expression levels of TGFβ_(1),TAK_(1),and p-p38 in the heart tissue of the CHF rat ***:These findings indicate that QXHLF has a therapeutic effect on CHF by inhibiting the p38-MAPK signaling pathway,reducing m

关键词： chronic heart failure Qiangxinhuoli prescription p38MAPK pathway H_(9)C_(2) Action mechanism

Feasibility of Scaling up the Cost-Competitive and Clean Electrolytic Hydrogen Supply in China

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Engineering 2024年第8期39卷 154-165页

作者： Guangsheng pan Wei Gu Zhongfan Gu Jin Lin Suyang Zhou zhi Wu Shuai Lu School of Electrical Engineering Southeast UniversityNanjing 210096China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

Scaling up clean hydrogen supply in the near future is critical to achieving China’s hydrogen development *** study established an electrolytic hydrogen development mechanism considering the generation mix and operation optimization of power systems with access to *** on the incremental cost principle,we quantified the provincial and national clean hydrogen production cost performance levels in *** results indicated that this mechanism could effectively reduce the production cost of clean hydrogen in most provinces,with a national average value of less than 2 USDkg1 at the 40-megaton hydrogen supply *** cooperation via power transmission lines could further reduce the production cost to 1.72 USD·kg^(-1).However,performance is affected by the potential distribution of hydrogen *** the supply side,competitiveness of the mechanism is limited to clean hydrogen production,while from the demand side,it could help electrolytic hydrogen fulfil a more significant *** study could provide a solution for the ambitious development of renewables and the hydrogen economy in China.

关键词： Low-carbon energy system Electrolytic hydrogen Renewables Cost optimization and analysis

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