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transcranial electrical stimulation in neurological disease

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Neural Regeneration Research 2022年第10期17卷 2221-2222页

作者： Gregory l.Brown Michael t.Brown Neurished HersheyPAUSA

Increased lifespan is one of society’s greatest achievements,but this longevity increases the prevalence of diseases of aging,such as neurological ***,neurological disorders are the leading cause of disability and the second leading cause of deaths(Feigin et al.,2019).Furthermore,these diseases affect people in low-,medium-,and high-income countries(Feigin et al.,2019).Current technology to modify neurological burden is scarce,which poses numerous challenges for healthcare,global policy,and economic stability(Feigin et al.,2019).to face these challenges,brain stimulation technology,such as transcranial electrical stimulation(tES),has displayed exciting *** et al.(2017)provide a detailed overview of the safety and application of ***,electrodes are attached to the head and a weak current(e.g.,1-2 mA)is applied through the scalp,skull,and into the brain for 10-30 minutes to activate neurons(Ant.l.et al.,2017).the technique is extremely safe with no serious adverse effects reported from thousands of sessions(Ant.l.et al.,2017).the most common side effects are a tingling/itching sensation or redness at the stimulation site(Ant.l.et al.,2017).However,these side effects can be minimized by reducing the electrode-skin impedance,slowly ramping up and ramping down tES,or using topical analgesics(Ant.l.et al.,2017).the development of tES may repair neural dysfunction and stem the oncoming incidence of neurodegenerative disease.

关键词： stimulation sensation electrical

Enhanced Heat transfer with Full Circumferential Ribs in Helical Pipe

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Journal of thermal Science 2002年第3期11卷 241-248页

作者： S.W.Chang l.M.Su t.l.Yang Department of Marine Engineering National Kaohsiung Institute of Marine Technology Kaohsiung Taiwan China Associate Professor Department of Electrical Engineering Tong Fang College of Technology and Commerce Taiwan China Associate Professor and Head of Department Department of Electrical Engineering Fortune Institute of Technology Taiwan China

this paper describes an experiment.l.study of heat transfers in the smooth-walled and rib-roughened helical pipes with reference to the design of enhanced cooling passages in the cylinder head and liner of a marine propulsive diesel engine. the manner in which the repeated ribs modify the forced heat convection in the helical pipe is considered for the case where the flow is turbulent upon entering the coil but.l.minar in further downstream. A selection of experiment.l.results illustrates the individual and interactive effects of Dean vortices and rib-flows on heat transfer along the inner and outer helixes of coils. the experiment.l.based observations reveal that the centrifugal force modifies the heat transfer in a manner to generate circumferential heat transfer variation with better cooling performance on the outer edge relative to its inner counterpart even with the agitated flow field caused by the repeated ribs. Heat transfer augmentation factor in the range of 1.3 ~ 3 times of the smooth-walled

关键词： helical pipe heat transfer enhancement.

Sediment.l.ads response to climate change:A preliminary study of eight.l.rge Chinese rivers

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International Journal of Sediment Research 2013年第1期28卷 1-14页

作者： X.X.lU l.S.RAN S.lIU t.JIANG S.R.ZHANG J.J.wang Department of Geography National University of Singapore117570Singapore Global Change and Watershed Management Center Yunnan University of Finance and EconomicsYunnan National Climate Centre China Meteorological AdministrationBeijingChina College of Water Sciences Beijing Normal UniversityChina

Climate change characterized by increasing temperature is able to affect precipitation regime and thus surface ***,the manner in which river sediment.l.ads respond to climate change is not well understood,and related assessment regarding the effect of climate change on sediment.l.ads is *** present a quantitative estimate of changes in sediment.l.ads(from 1.5 Gt yr-1pre-1990 to 0.6 Gt yr-1from 1991-2007) in response to climate change in eight.l.rge Chinese *** the past decades,precipitation change coupled with rising temperatures has played a significant role in influencing the sediment delivery dynamics,although human activities, such as reservoir construction,water diversion,sand mining and land cover change,are st.l. the predominant forces. lower precipitation coupled with rising temperatures has significantly reduced sediment.l.ads delivered into the sea in semi-arid climates(4-61%).In contrast,increasingly warmer and wetter climates in subtropical zones has yielded more sediment(0.4-11%),although the increase was offset by human *** results indicate that,compared with mechanical retention by reservoirs,water reduction caused by climate change or human withdrawals has contributed more sediment reduction for the rivers with abundant sediment supply but.l.mited transport capacity(e.g.,the Huanghe).Furthermore,our results indicate that every 1%change in precipitation has resulted in a 1.3%change in water discharge and a 2%change in sediment *** addition,every 1%change in water discharge caused by precipitation has led to a 1.6%change in sediment.l.ads,but the same percentage of water discharge change caused largely by humans would only result in a 0.9%change in sediment *** figures can be used as a guideline for evaluating the responses of sediment.l.ads to climate change in similar climate zones because future global warming will cause dramatic changes in water and sediment in river basins worldwide at rates previou

关键词： Sediment.l.ad Climate change Human activity Water withdrawal Chinese rivers

Oil charging history and pathways of the Ordovician carbonate reservoir in the tuoputai region,tarim Basin,NW China

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Petroleum Science 2017年第4期14卷 662-675页

作者： Rong-Hui Fang Mei-Jun li Hai-tao lü t.-G.wang Yuan Yuan Yong-li liu Zhi-Yong Ni State Key laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing 102249China Exploration and Development Research Institute Northwest Oilfield Branch CorporationSINOPECUrumqi 830011XinjiangChina Research Institute of Shaanxi Yanchang Petroleum(Group)Co.ltd Xi'an 710075ShaanxiChina

Geochemical analysis of 64 oils sampled from an Ordovician carbonate reservoir in the tuoputai region was undertaken to study the composition of molecular markers. All the oils have similar geochemical characteristics and belong to a single oil family. they are presumed to derive from the same source kitchen and have similar oil charging history. A histogram of homogenization temperatures(th) of aqueous inclusions in reservoir rocks shows a bimodal distribution pattern, indicating that the Ordovician reservoir has been charged twice. Coupling the measured th(°C) with the burial and geothermal histories reconstructed using 1D basin modeling, we relate the homogenization temperature to the relevant geological ages: i.e.,425–412 and 9–4 Ma, corresponding to the Middle to late Silurian and the Miocene to Pliocene, respectively. the oil filling orientation and pathways are traced using molecular indicators related to alkyldibenzothiophenes and benzo[b]naphthothiophenes. the oil charging orientation is from south to north generally. It can be predicted that the Ordovician reservoirs were sourced from a kitchen located to the south of the tuoputai region, most probably between the Awati and Manjiaer Depressions. traps located in the southern side of the tuoputai region, along the oil charging pathways, should therefore be preferred oil exploration targets.

关键词： Oil population Oil charging events Fluid inclusion 1D numerical modeling Oil filling pathway

Combined approach for analysing evolutionary power spectra of a track-soil system under moving random loads

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Acta Mechanica Sinica 2019年第3期35卷 674-690页

作者： Y.Zhao l.t.Si H.Ouyang State Key laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Center for Computational MechanicsDalian University of TechnologyDalian 116023Chin School of Engineering University of LiverpoolLiverpool L69 3GHUK

the pseudo-excitation method combined with the integral transform method (PEM-ItM) is presented to investigate the ground vibration of a coupled track-soil system induced by moving random loads. Commonly in the track model, the rail, sleepers, rail pads, and ballast are modelled as an infinite Euler beam, discret.l. distributed masses, discret.l. distributed vertical springs, and a viscoelastic layer, respectively. the soil is regarded as a homogenous isotropic half-space coupled with the track using the boundary condition at the surface of the ground. By introducing a pseudo-excitation, the random vibration analysis of the coupled system is converted into a harmonic analysis. the analytical form of evolutionary power spectral density responses of the simplified coupled track-soil system under a random moving load is derived in the frequency/wavenumber domain by PEM-ItM. In the numerical examples, the effects of different parameters, such as the moving speed, the soil properties, and the coherence of moving loads, on the ground response are investigated.

关键词： track-soil system Moving random loads Evolutionary power spectrum Pseudo-excitation method Integral transform method Vibration transmission

Flow instability of nanofuilds in jet

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Applied Mathematics and Mechanics(English Edition) 2015年第2期36卷 141-152页

作者： Yi XIA Jianzhong lIN Fubing BAO t.l.CHAN Department of Mechanics State Key Laboratory of Fluid Power Transmission and ControlZhejiang University Institute of Fluid Mechanics China Jiliang University Department of Mechanical Engineering The Hong Kong Polytechnic University

the flow instability of nanofluids in a jet is studied numerically under various shape factors of the velocity profile, Reynolds numbers, nanoparticle mass loadings,Knudsen numbers, and Stokes numbers. the numerical results are compared with the available theoretical results for validation. the results show that the presence of nanoparticles enhances the flow stability, and there exists a critical particle mass loading beyond which the flow is stable. As the shape factor of the velocity profile and the Reynolds number increase, the flow becomes more unstable. However, the flow becomes more stable with the increase of the particle mass loading. the wavenumber corresponding to the maximum of wave amplification becomes large with the increase of the shape factor of the velocity profile, and with the decrease of the particle mass loading and the Reynolds number. the variations of wave amplification with the Stokes number and the Knudsen number are not monotonic increasing or decreasing, and there exists a critical Stokes number and a Knudsen number with which the flow is relatively stable and most unstable,respectively, when other parameters remain unchanged. the perturbation with the first azimuthal mode makes the flow unstable more easily than that with the axisymmetric azimuthal mode. the wavenumbers corresponding to the maximum of wave amplification are more concentrated for the perturbation with the axisymmetric azimuthal mode.

关键词： nanoparticle-laden jet flow hydrodynamic instability Stokes number Knudsen number particle mass loading

StUDY OF RAY IRRADIAtION ON DIAMOND-lIKE CARBON FIlMS

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Acta Met.l.urgica Sinica(English letters) 2002年第1期15卷 26-32页

作者： G.A. liu t.M. wang E.Q Dept. of Appl. Phy. Southwest Jiaotong Univ. Chengdu 610031 China

Diamond-like carbon (DlC) films have been deposited on glass substrates usingradio-frequency (rf) plasma deposition method. Gamma -ray, ultraviolet (UV) ray were used toirradiate the DlC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe changing characteristics of SP^3 C-H bond and hydrogen content in the films due to theirradiations. the results show that, the damage degrees induced by the UV ray on the SP^3 C-H bondsare much stronger than that by the gamma -ray. When the irradiation dose of gamma -ray reaches 1 OX10^4 Gy, the SP^3 C-H bond reduces about 50 percent in number. the square electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using the results on optical gap of the films and the fully constrained network theory,the hydrogen content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film gamma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance

High-pressure granulite from Western Kunlun,northwestern China:Its metamorphic evolution,zircon SHRIMP U-Pb ages and tectonic implication

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Science China Earth Sciences 2007年第7期50卷 961-971页

作者： QU JunFeng ZHANG liFei AI Yongliang l Zeng wang JianPing ZHOU Hui wang ShiYan MOE Key laboratory of Orogenic Belts and Crust.l.Evolution School of Earth and Space SciencePeking UniversityBeijing 100871China Henan Polytechnic University Jiaozuo 454100China Geological Survey of Henan Province Zhengzhou 450007China

High-pressure mafic granulites occurring as lenticular bodies within garnet-amphibolites in Kangxiwar Fault have been first reported in this paper. the P-t conditions of two metamorphic stages were obtained using calibrated geothermal barometers and thermoCalc Program. the peak metamorphic condition of these high-pressure granulites is about 760–820°C, 1.0–1.2 GPa and the retrograde metamorphic condition is about 620–720°C, 0.7–0.8 GPa. the petrological studies show that they have a near-isobaric cooling P-t path which suggests that the Western Kunlun underwent initial crust.l.thickening, subsequent exhumation and cooling. the SHRIMP zircon U-Pb dating gives two groups of ages for high-pressure granulites. One is 177±6 Ma which is obtained from the rim of the zircon. We consider this age should be the metamorphic age. And the other is 456±30 Ma which is obtained from the core of the zircon and should be the prot.l.th age. the formation of these high-pressure granulites in western Kunlun is closely correlated with the evolution of the Paleo-tethys and has important implications for the research on tethys and Paleo-Asian tectonic zone.

关键词： Western Kunlun Kangxiwar Fault high-pressure granulite P-t path SHRIMP U-Pb dating of zircon

PRECIPItAtION AND GROWtH OF PEROVSKItE PHASE IN tItANIUM BEARING BlASt FURNACE SlAG

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Acta Met.l.urgica Sinica(English letters) 2007年第1期20卷 9-14页

作者： Z.Z. Guo t.P. lou l. Zhang l.N. Zhang Z.t. Sui School of Materials and Met.l.urgy Northeastern University Shenyang 110006 Ghina

the effects of transformation of slag composition and additive agents on the morphology, the precipitation behavior, the cryst.l.growth, and the volume fraction (VF) of perovskite (CaO·¤tiO_2) cryst.l.in the ti-bearing blast furnace slags were investigated. As the morphology of perovskite is dispersed in molten slags, the cryst.l.growth mechanism of the melting of fine dendrites and the coarsening of large grains exist throughout the solidification of molten slags. With the increase of CaO and Fe_2O_3 content, VF of perovskite obviously increases. However, high basicity leads to the viscosity of slag, which results in the reduction of the average equivalent diameter (AED). the experiment.l.results showed that the presence of the additives CaF_2 and MnO efficiently decreased the viscosity of the slags, and obviously improved the morphology of perovskite and promoted its growth.

关键词： perovskite phase ti-bearing blast furnace slag precipitation additive agent