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Subgroup Separability of Certain Generalized Free Products of Nilpotent-by-finite Groups

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1199-1204页

作者： Wei Zhou Goansu KIM School of Mathematics and Statistics Southwest University Department of Mathematics Yeungnam University

In this paper, we show that certain generalized free products of nilpotent-by-finite groups are subgroup separable when the amalgamated subgroup is × D where D is in the center of both factors.

关键词： Generalized free products residually finite subgroup separable nilpotent groups

Influence of the pace of El Nino decay on tropical cyclone frequency over the western north pacific during decaying El Nino summers

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 39-45页

作者： Qun zhou Lixin wei National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijingChina

本文分析了El Nino事件衰减速度的差异对衰退年夏季西北太平洋热带气旋(tropical cyclone,TC)频数的不同影响。按照ElNiio事件衰减速度不同,将其划分为迅速衰减(rapid decaying,RD)和缓慢衰减(slowdecaying,SD)的El Nino事件.SD(RD)El N... 详细信息

本文分析了El Nino事件衰减速度的差异对衰退年夏季西北太平洋热带气旋(tropical cyclone,TC)频数的不同影响。按照ElNiio事件衰减速度不同,将其划分为迅速衰减(rapid decaying,RD)和缓慢衰减(slowdecaying,SD)的El Nino事件.SD(RD)El Nino事件的衰退年夏季,赤道中东太平洋海温仍维持正异常(衰减为负异常).与SD El Nino事件相比,RDElNino事件衰退年夏季西北太平洋TC频数显著减少.进一步的分析揭示了导致TC频数差异的大尺度环境要素,指出热带印度洋-太平洋海温异常密切相关的西北太平洋低层反气旋异常在其中起到了关键作用。

关键词： ElNino衰减速度热带气旋西北太平洋低层反气旋

Product platform architecture for cloud manufacturing

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Advances in Manufacturing 2020年第3期8卷 331-343页

作者： wei wei Feng zhou Peng-Fei Liang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191People’s Republic of China

Cloud manufacturing is emerging as a new manufacturing paradigm and an integrated technology.To adapt to the increasing challenges of the traditional manufacturing industry transforming toward service-oriented and innovative manufacturing,this paper proposes a product platform architecture based on cloud manufacturing.Firstly,a framework for the product platform for cloud manufacturing was built.The proposed architecture is composed of five layers:resource,cloud technology,cloud service,application,and user layers.Then,several key enabling technologies for forming the product platform were studied.Finally,the product platform for cloud manufacturing built by a company was taken as an application example to illustrate the architecture and functions of the system.The validity and superiority of the architecture were verified.

关键词： Cloud manufacturing Cloud service Product platform Architecture Product collaborative design

Geochemical characteristics of cold-seep carbonates in Shenhu area,South China Sea

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Journal of Oceanology and Limnology 2022年第3期40卷 969-985页

作者： Chongmin CHEN Lifeng ZHONG Zhifeng WAN Chiyu CHENG Wei Zhou Xing XU School of Marine Sciences Guangdong Provincial Key Laboratory of Marine Resources and Coastal EngineeringSun Yat-sen UniversityZhuhai 519000China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyMinistry of Natural ResourcesGuangzhou 510075China

Cold seeps spread worldwide along the continental margins,which are closely related to the exploration of gas hydrates.Cold-seep carbonates have been reported to record the nature of seepage,including fluid source,sedimentary environment,and variation of seepage activity.We investigated the morphology,mineralogy,element compositions,and carbon and oxygen isotopes of 15 cold-seep carbonates collected from the Shenhu area,and compared them with 2 carbonates from the Haima cold seep,the South China Sea(SCS),to promote our knowledge of cold-seep system in SCS.Most of the Shenhu carbonates exhibit crust morphology,and some are in the form of chimneys and blocks.Their absolute(20%–65%)and relative carbonate mineral contents(mainly aragonite and calcite,with minor samples containing dolomite)vary significantly,indicating the multi-stage methane leakage in our study area.Some samples show a slight negative Ce anomaly,suggesting either the mixing of seawater or variation of the redox condition during the precipitation;the cooccurrence of strongly enriched U and Mo demonstrates anoxic condition during precipitation.The mixed genetic methane source was interpreted by δ^(13)C of the Shenhu carbonates to range from-22.34‰to-59.30‰Vienna PeeDee Belemnite(VPDB),and the slight ^(18)O-enrichment imprinted on the carbonates suggests the possible influence from hydrate dissociation.The Haima carbonates,with biogenic methane as the main gas source,were presumably formed in a stronger fluid flux by compared with our Shenhu samples.

关键词： cold-seep carbonates geochemistry sedimentary environment fluid source Haima cold seep Shenhu area South China Sea

Why 90%of clinical drug development fails and how to improve it?

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Acta Pharmaceutica Sinica B 2022年第7期12卷 3049-3062页

作者： Duxin Sun wei Gao Hongxiang Hu Simon zhou Department of Pharmaceutical Sciences College of PharmacyUniversity of MichiganAnn ArborMI48109USA Translational Development and Clinical Pharmacology Bristol Meyer Squibb CompanySummitNJ07920USA

Ninety percent of clinical drug development fails despite implementation of many successful strategies,which raised the question whether certain aspects in target validation and drug optimization are overlooked?Current drug optimization overly emphasizes potency/specificity using structure-activityrelationship(SAR)but overlooks tissue exposure/selectivity in disease/normal tissues using structure-tissue exposure/selectivity—relationship(STR),which may mislead the drug candidate selection and impact the balance of clinical dose/efficacy/toxicity.We propose structure-tissue exposure/selectivity—activity relationship(STAR)to improve drug optimization,which classifies drug candidates based on drug’s potency/selectivity,tissue exposure/selectivity,and required dose for balancing clinical efficacy/toxicity.ClassⅠdrugs have high specificity/potency and high tissue exposure/selectivity,which needs low dose to achieve superior clinical efficacy/safety with high success rate.ClassⅡdrugs have high specificity/potency and low tissue exposure/selectivity,which requires high dose to achieve clinical efficacy with high toxicity and needs to be cautiously evaluated.ClassⅢdrugs have relatively low(adequate)specificity/potency but high tissue exposure/selectivity,which requires low dose to achieve clinical efficacy with manageable toxicity but are often overlooked.ClassⅣdrugs have low specificity/potency and low tissue exposure/selectivity,which achieves inadequate efficacy/safety,and should be terminated early.STAR may improve drug optimization and clinical studies for the success of clinical drug development.

关键词： Drug development Drug optimization Clinical trial Structure-tissue exposure/selectivity relationship(STR) Structure-tissue exposure/selectivity—activity relationship(STAR)

Prototype of single-event effect localization system with CMOS pixel sensor

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Nuclear Science and Techniques 2022年第11期33卷 10-20页

作者： Jun Liu Zhuo zhou Dong Wang Shi-Qiang zhou Xiang-Ming Sun wei-Ping Ren Bi-Hui You Chao-Song Gao Le Xiao Ping Yang Di Guo Guang-Ming Huang Wei Zhou Cheng-Xin Zhao Min Wang PLAC Key Laboratory of Quark&Lepton Physics(MOE)Central China Normal UniversityWuhan 430079China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The single-event effect(SEE) is a serious threat to electronics in radiation environments. The most important issue in radiation-hardening studies is the localization of the sensitive region in electronics to the SEE. To solve this problem, a prototype based on a complementary metal oxide semiconductor(CMOS) pixel sensor, i.e., TopmetalM, was designed for SEE localization. A beam test was performed on the prototype at the radiation terminal of the Heavy Ion Research Facility in Lanzhou(HIRFL). The results indicated that the inherent deflection angle of the prototype to the beam was 1.7°, and the angular resolution was 0.6°. The prototype localized heavy ions with a position resolution of 3.4 μm.

关键词： Single-event effect Radiation resistant Topmetal-M

Numerical Investigation on Dropwise Condensation on Rough Structures with and without Non-Condensable Gas

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Journal of Thermal Science 2022年第2期31卷 308-317页

作者： LI Mingjie zhou Wenjing wei Jinjia TAO Wenquan School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an710049China Key Laboratory of Thermo-Fluid Science and Engineering Ministry of EducationSchool of Energy&Power EngineeringXi’an Jiaotong UniversityXi’an710049China

The geometrical dimensions of the rough structures as well as the non-condensable gases in the vapor mixture can have the great effect on the nucleation position and the wetting state of the droplet,which further influence the condensation heat flux.In this paper,the multispecies multiphase lattice Boltzmann method together with a thermal phase change model is used to investigate the dropwise condensation on a rough surface enhanced with pillars.The effect of the geometric dimensions including pillar height H,pillar width W and pillar space S is investigated.Then the effect of non-condensable gases on the contact angle of a droplet on textured surface is studied.The results show that the local heat flux and the wetting area are higher while the waiting time is shorter at larger S,W and smaller H on the rough surface.The nucleation position rises from the bottom of grooves to the top with the increase of pillar height and the decrease of pillar space.The contact angle is larger and it is easier to maintain the Cassie state for droplet.When there exists non-condensable gas,the non-condensable gas obviously enhances the hydrophobicity of the rough surfaces compared with pure vapor.

关键词： 1condensation wetting state lattice Boltzmann method numerical simulation

Numerical study on butterfly wings around inclusion based on damage evolution and semi-analytical method

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Friction 2022年第9期10卷 1335-1352页

作者： Ye zhou Caichao ZHU Xiaojin CHEN wei YE State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400030China College of Aerospace Engineering Chongqing UniversityChongqing 400044China Chongqing Wangjiang Industrial Co. Chongqing 400071China

Butterfly wings are closely related to the premature failure of rolling element bearings.In this study,butterfly formation is investigated using the developed semi-analytical three-dimensional(3D)contact model incorporating inclusion and material property degradation.The 3D elastic field introduced by inhomogeneous inclusion is solved by using numerical approaches,which include the equivalent inclusion method(EIM)and the conjugate gradient method(CGM).The accumulation of fatigue damage surrounding inclusions is described using continuum damage mechanics.The coupling between the development of the damaged zone and the stress field is considered.The effects of the inclusion properties on the contact status and butterfly formation are discussed in detail.The model provides a potential method for quantifying material defects and fatigue behavior in terms of the deterioration of material properties.

关键词： contact fatigue butterfly wings semi-analytical method damage evolution

Ba3LaNa(PO4)3F:Tm^3+,Dy^3+:A tunable blue-white color emitting phosphor via energy transfer for UV white LEDs

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Chinese Chemical Letters 2020年第2期31卷 575-578页

作者： Dingdian Xu Wei Zhou Shujing Li Dongsheng Bai Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business UniversityBeijing 100048China Department of Chemistry School of ScienceBeijing Technology and Business UniversityBeijing 100048China

A series of Tm^3+/Dy^3+co-doped Ba3 LaNa(PO4)3 F(BLNPF) phosphors were synthesized successfully via a high-temperature solid-reaction,and luminescence properties were investigated.Upon near violet excitation,BLNPF:Tm^3+,Dy^3+ phosphors exhibit Tm^3+:^1D2-^3 F4 and Dy^3+:^4 F(9/2)-^6 HJ(J=15/2,13/2,11/2)transitions with diffe rent luminescence intensity.The emitting color of the obtained products was found to shift from blue to white as a result of efficient energy transfer(ET) from Tm^3+to Dy^3+ions.According to photoluminescence emission intensity,the positive effect of activator on ET efficiency was calculated and the maximum ET efficiency was found around 72.6% with Dy^3+ concentration was 0.04.By means of Dexter's theoretical model,furthermore,dipole-dipole interaction was confirmed as the mechanism of energy transfer from Tm^3+ to Dy^3+ ions.The results suggested that BLNPF:Tm^3+,Dy^3+ phosphor might be a promising single-phased white-light-emitting phosphor for UV white-light LED.

关键词： Phosphors Ba3LaNa(PO4)3F Luminescence Energy transfer White light