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npj Computational Materials 2021年第1期7卷 1299-1319页

作者： Talha Qasim Ansari Haitao huang San-qiang Shi Department of Applied Physics and Research Institute of Smart Energy the Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SAR Department of Mechanical Engineering the Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SAR

The complex degradation of metallic materials in aggressive environments can result in morphological and microstructural *** phase-field(PF)method is an effective computational approach to understanding and predicting the morphology,phase change and/or transformation of *** models are based on conserved and non-conserved field variables that represent each phase as a function of space and time coupled with time-dependent equations that describe the *** report summarizes progress in the PF modeling of degradation of metallic materials in aqueous corrosion,hydrogen-assisted cracking,high-temperature metal oxidation in the gas phase and porous structure evolution with insights to future applications.

关键词： corrosion cracking metallic

EXTENDED WARRANTY STRATEGIES FOR ONLINE SHOPPING SUPPLY CHAIN WITH COMPETING SUPPLIERS CONSIDERING COMPONENT RELIABILITY

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Journal of Systems Science and Systems Engineering 2017年第6期26卷 753-773页

作者： Xinghong Qin qiang Su Samuel H. huang School of Economics and Management Tongji University Shanghai China School of Business Planning Chongqing Technology and Business University Chongqing China Department of Mechanical and Materials Engineering University of Cincinnati Cincinnati USA

This article presents the issue of extended warranty and management strategies in a three-echelon competing online shopping supply chain with price- and base warranty period-dependent demand. We employ game theory to develop decision models to explore the interactions between component suppliers and the manufacturer, as well as competition between two component suppliers. Products and extended warranty are sold by an online store, which is the leader in the Stackelberg game. Two scenarios are considered： either the manufacturer offers a prepaid extended warranty to customers or doses not. In each scenario, base warranties are assumed to be bundled with products. Our results show that when the manufacturer＇s repair costs change in a proper range, providing extended warranty can benefit both the manufacturer and the online store; otherwise, the manufacturer has no incentive to offer the extended warranty. Reducing repair costs, improving component reliability, or shortening the base warranty period allows the manufacturer to realize significantly better value of the extended warranty. High component reliability benefits both the manufacturer and the online store, with the manufacturer reaping more benefit. Extending the length of the base warranty adversely affects profit of the manufacturer and the value of the extended warranty.

关键词： Extended warranty online shopping supply chain game theory online shopping

Control of vortex-induced vibrations of the cylinder by using split-ter plates immersed in the cylinder wake at low Reynolds number

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Journal of Hydrodynamics 2020年第5期32卷 942-952页

作者： Zhi-qiang Xin Zhi-huang Wu Chui-jie Wu Dan huang The College of Mechanics and Materials HoHai UniversityNanjing 211100China State Key Laboratory of Structural Analysis for Industrial Equipment and School of Aeronautics and Astronautics Dalian University of TechnologyDalianChina

The vortex-induced vibrations of a cylinder with two plates symmetrically distributed along the centerline of the wake are studied by using the fluid-structure interaction simulations on the Arbitrary Lagrangian-Eulerian *** this study,the different geo-metrical distribution parameters of the splitter plates and inflow velocities are taken into *** physical mechanisms of vortex-induced vibration of the cylinder with symmetrical plates are revealed from the cylinder amplitude,hydrodynamic force characteristics,vortex shedding frequency,and flow pattern *** results show that the dynamic interaction between the vortex shed from the oscillation cylinder and plates is responsible for the wake stabilization mechanism,and the stable wake and the dynamic response reduction of the main cylinder can be achieved at a wide range of reduced velocities by placing sym-metrical sheets at suitable locations.

关键词： Cylinder vortex-induced vibrations splitter plates vibration control flow pattern

Investigate the effects of magnetic fields on the penetration ability of a shaped charge jet at different standoffs

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Defence Technology（防务技术） 2021年第5期17卷 1722-1730页

作者： Bin Ma Zheng-xiang huang Zhong-wei Guan Xin Jia Xu-dong Zu qiang-qiang Xiao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China School of Engineering University of LiverpoolLiverpoolL693GQUK

The influence of a magnetic field on the stability of a shaped charge jet is experimentally investigated at standoffs of 490,650 and 800 *** experimental results without and with the magnetic field are compared in terms of the shaped charge jet form,stability and penetration ability.A theoretical model based on one-dimension fluid dynamics is then developed to assess the depth of penetration of the shaped charge at those three standoffs and magnetic *** results show that the penetration capability can be enhanced in more than 70%by the magnetic *** theoretical calculations are compared with the experimental results with reasonably good *** addition,the parameters introduced in the theory are discussed together with the experiments at three standoffs studied.

关键词： Shaped charge jet Stability Penetration Magnetic field Coupling mechanism

Cross-Coupling of Secondary Amides with Tertiary Amides: The Use of Tertiary Amides as Surrogates of Alkyl Carbanions for Ketone Synthesis

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Chinese Journal of Chemistry 2019年第9期37卷 887-891页

作者： Shu-Ren Wang Pei-qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China

In recent years,exciting progress has been made in the field of direct transformation of amides,nevertheless,the condensation between two amides remains rare and restricted to homo-coupling ***,we report the cross-coupling of secondary amides with tertiary amides,which provides a synthesis of ketones under mild conditions,and features the use of tertiary amides as surrogates of alkyl *** method relies on the coupling of enamines,generated from tertiary amides by catalytic partial reduction of tertiary amides with Vaska's catalyst,with nitrilium ions,formed in situ from secondary amides via activation with trifluoromethanesulfonic anhydride,and on the subsequent deformylation.

关键词： Secondary Amides Tertiary Amides Alkyl Carbanions

Orbital Forcing and Sea-Level Changes in the Earliest Triassic of the Meishan Section,South China

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Journal of Earth Science 2014年第1期25卷 64-73页

作者： Shifeng Tian Zhong-qiang Chen Chunju huang Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences Faculty of Earth Resources China University of Geosciences State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Faculty of Earth Sciences China University of Geosciences

The Earliest Triassic Yinkeng Formation is exposed at the well-known Meishan Section, South China, which contains the Global Stratotype of Section and Point （GSSP） for the Permian- Triassic boundary （PTB）. It records centimeter-scale rhythmic alternations comprised mainly by marl- stone and limestone. Seven types of couplet embedded in five types of bundles were recognized based on occurrence and thickness of the lithologic units, suggesting that their formation was controlled by cyclic processes. The various orders of cycles observed correlate well with other Early Triassic counterparts recorded in South China. Here, we present new cyclostratigraphic results based on lithologic thickness and relative carbonate content of the Yinkeng Formation. Power spectra of carbonate content show that the ratio of major wavelengths recognized throughout the formation is similar to that of the 100 kyr short eccentricity, 33 kyr obliquity, and 21 kyr precession cycles, indicating that astronomical sig- nals are recorded in the Earliest Triassic rhythmic succession. Consistence between pronounced lithologic rhythmicity and sea-level changes obtained from Fischer plots indicates that high-frequency climatic cycles may have driven sea-level changes immediately after the PTB mass extinction. Fur- thermore, the 4th-order sea-level changes interpreted from the sedimentary record match well with 100 kyr short eccentricity component of carbonate content, reflecting that the 100 kyr short eccentricity- induced climate changes may have likely controlled the deposition of 4th-order sequences recognized from rhythmic successions.

关键词： orbital cycle limestone-marl alternation carbonate content Fischer plot Yinkeng Formation.

Circular RNA hsacirc0000745 may serve as a diagnostic marker for gastric cancer

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World Journal of Gastroenterology 2017年第34期23卷 6330-6338页

作者： Mei huang Yi-Ren He Li-Chuan Liang qiang huang Zhi-qiang Zhu Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery Department of General SurgeryAnhui Provincial Hospital Affiliated to Anhui Medical University Department of General Surgery Anhui Provincial Hospital Affiliated to Anhui Medical University

AIM To determine whether circular RNAs(circ RNAs) are involved in pathological processes of gastric cancer(GC).METHODS Three circ RNAs with differential expression in GC and colorectal cancer were randomly selected for validation by quantitative reverse transcription-polymerase chain reaction(q RT-PCR), using 20 pairs of gastric tissues and normal tissues. Based on the predicted circ RNAmi RNA network, we then focused on hsa_circ_0000745, which was found to be down-regulated in 20 GC tissues compared with normal tissues. The hsa_circ_0000745 levels were further analyzed by q RT-PCR in 60 GC tissues and paired adjacent non-tumor tissues, as well as 60 plasma samples from GC patients and 60 plasma samples from healthy controls. The associations between the levels of hsa_circ_0000745 and the clinicopathological features of GC patients were statistically assessed. A receiver operating characteristic(ROC) curve was used to evaluate the diagnostic value of hsa_circ_0000745 in *** Hsa_circ_0000745 was down-regulated in GC tissues vs non-tumorous tissues(P < 0.001) and in plasma samples from patients with GC vs healthy controls(P < 0.001). The expression level of hsa_circ_0000745 in GC tissues correlated with tumor differentiation, while the expression level in plasma correlated with tumor-nodemetastasis stage. The area under the ROC curve(AUC) of hsa_circ_0000745 in plasma was 0.683, suggesting good diagnostic value. Plasma hsa_circ_0000745 level combined with carcinoembryogenic antigen(CEA) level increased the AUC to *** Hsa_circ_0000745 plays an important role in GC and its expression level in plasma in combination with CEA level is a promising diagnostic marker for this malignancy.

关键词： Circular RNA circ_0000745 Gastric cancer Diagnosis Noncoding RNA

Revisiting the Evolutionary History of Pigs via De Novo Mutation Rate Estimation in A Three-generation Pedigree

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Genomics, Proteomics & Bioinformatics 2022年第6期20卷 1040-1052页

作者： Mingpeng Zhang qiang Yang Huashui Ai Lusheng huang State Key Laboratory of Swine Genetic Improvement and Production Technology Jiangxi Agricultural UniversityNanchang 330045China

The mutation rate used in the previous analyses of pig evolution and demographics was cursory and hence invited potential bias in inferring evolutionary ***,we estimated the de novo mutation rate of pigs as 3.6×10-9 per base per generation using high-quality whole-genome sequencing data from nine individuals in a three-generation pedigree through stringent filtering and *** this mutation rate,we re-investigated the evolutionary history of *** estimated divergence time of~10 kiloyears ago(KYA)between European wild and domesticated pigs was consistent with the domestication time of European pigs based on archaeological ***,other divergence events inferred here were not as ancient as previously *** estimates suggest that Sus speciation occurred~1.36 million years ago(MYA);European wild pigs split from Asian wild pigs only~219 KYA;and south and north Chinese wild pigs split~25 ***,our results showed that the most recent divergence event between Chinese wild and domesticated pigs occurred in the Hetao Plain,northern China,approximately 20 KYA,supporting the possibly independent domestication in northern China along the middle Yellow *** also found that the maximum effective population size of pigs was~6 times larger than estimated *** archaic migration from other Sus species originating~2 MYA to European pigs was detected during western colonization of pigs,which may affect the accuracy of previous demographic *** de novo mutation rate estimation and its consequences for demographic history inference reasonably provide a new vision regarding the evolutionary history of pigs.

关键词： Pig De novo mutation rate Three-generation pedigree Evolutionary history Archaic migration

Tf_2O-TMDS combination for the direct reductive transformation of secondary amides to aldimines,aldehydes, and/or amines

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Science China Chemistry 2016年第12期59卷 1638-1644页

作者： Qi-Wei Lang Xiu-Ning Hu Pei-qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University

The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette's method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine,and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane(TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields,and yields(NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot,the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.

关键词： secondary amides amide activation partial reduction aldimines N-deacylation

Effective methods for isolation and purification of extracellular vesicles from plants

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Journal of Integrative Plant Biology 2021年第12期63卷 2020-2030页

作者： Yifan huang Shumei Wang qiang Cai Hailing Jin State Key Laboratory of Hybrid Rice College of Life ScienceWuhan UniversityWuhan 430072China Hubei Hongshan Laboratory Wuhan 430072China Department of Microbiology and Plant Pathology and Center for Plant Cell Biology Institute for Integrative Genome BiologyUniversity of CaliforniaRiversideCA 92507USA

Plant extracellular vesicles(EVs)play critical roles in the cross-kingdom trafficking of molecules from hosts to interacting microbes,most notably in plant defense ***,the isolation of pure,intact EVs from plants remains challenging.A variety of methods have been utilized to isolate plant EVs from apoplastic washing fluid(AWF).Here,we compare published plant EV isolation methods,and provide our recommended method for the isolation and purification of plant *** method includes a detailed protocol for clean AWF collection from Arabidopsis thaliana leaves,followed by EV isolation via differential *** further separate and purify specific subclasses of EVs from heterogeneous vesicle populations,density gradient ultracentrifugation and immunoaffinity capture are then *** found that immunoaffinity capture is the most precise method for specific EV subclass isolation when suitable specific EV biomarkers and their corresponding antibodies are ***,this study provides a guide for the selection and optimization of EV isolation methods for desired downstream applications.

关键词： cell-to-cell communication extracellular vesicles isolation methods plants interacting with pathogens