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Journal of Environmental Sciences 2019年第4期31卷 183-192页

作者： Yanjun zhang Changwei Zhao shaofeng zhang Ling Yu Jiding Li Li-an Hou School of Chemical Engineering Hebei University of Technology Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua University Xi'an High-Tech Institute

The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent *** important step is to remove different multivalent ions in salt ***(NF)has been used for treating water containing different kinds of *** this work,sulfonate group-modified graphene oxide(SGO)was prepared,and added during the interfacial polymerization(IP)reaction to prepare SGO-modifiedNF membranes(PA-SGO).The chemical composition,structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR,XPS,SEM,AFM,contact angle and zeta potential *** water flux,salt rejection and antifouling abilities were investigated *** testing results showed that the water flux of PA-SGO(0.03%SGO)was 45.85 LMH under a pressure of 0.2 MPa,and the salt rejection varied in the order of Na_2SO_4(98.99%)>MgSO_4(91.25%)>MgCl_2(42.27%)>NaCl(21.96%).An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and *** PA-SGO membrane has good potential for use in removing salt ions from water.

关键词： Water treatment Sulfonate group-modified graphene oxide NF Membrane Salt separation

Cenozoic basin development and its indication of plateau growth in the Xunhua-Guide district

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Science China Earth Sciences 2007年第z2期50卷 277-291页

作者： LIU shaofeng zhang GuoWei P.L.HELLER State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China College of Geosciences and Resources China University of Geosciences Beijing 100083 China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China Department of Geology Northwest University Xi'an 710069 China Department of Geology and Geophysics University of Wyoming Laramie Wyoming 82071 USA

The Xunhua, Guide and Tongren Basins are linked with the Laji Mountain and the northern West Qinling thrust belts in the Xunhua-Guide district. Basin depositional stratigraphy consists of the Oligocene Xining Group, the uppermost Oligocene-Pliocene Guide Group and the Lower Pleistocene. They are divided into three basin phases by unconformities. Basin phase 1 is composed of the Xining Group, and Basin phase 2 of the Zharang, Xiadongshan, Herjia and Ganjia Conglomerate Formations in the Guide Group, and Basin phase 3 of the Gonghe Formation and the Lower Pleistocene. Three basin phases all develop lacustrine deposits at their lower parts, and alluvial-braided channel plain depositional systems at upper parts, which constitute a coarsening-upward and progradational sequence. Basin deposition, paleocurrent and provenance analyses represent that large lacustrine basin across the Laji Mountain was developed and sourced from the West Qinling thrust belt during the stage of the Xining Group (Basin phase 1), and point-dispersed alluvial fan-braided channel plain deposition systems were developed beside the thrust and uplifted Laji Mountain and sourced from it, as thrusting migrated northwards during the stage of the Guide Group (Basin phase 2). Evolution of basin-mountain system in the study area significantly indicates the growth process of the distal Tibetan Plateau. The result shows that the Tibetan Plateau expanded to the northern West-Qinling at Oligocene (29―21.4 Ma) by means of northward folded-and-thrust thickening and uplifting and frontal foreland basin filling, and across the study area to North Qilian and Liupan Mountain at the Miocene-Pliocene (20.8―2.6 Ma) by means of two-sided basement-involved-thrust thickening and uplifting and broken foreland basin filling, and the distant end of Tibetan Plateau behaved as regional erosion and intermontane basin aggradational filling during the Pliocene and early Pleistocene (2.6―1.7 Ma).

关键词： Xunhua-Guide district, Cenozoic basins, provenance analysis, basin-mountain evolution, plateau growth

Constraint strength and axial/radial particle velocity profiles for an integrated riser outlet

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Particuology 2015年第4期13卷 179-186页

作者： Dewu Wang Chaoyu Yan Chunxi Lu Rui Li Bin Zhao shaofeng zhang School of Chemical Engineering Hebei University of Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum Engineering Research Center of Seawater Utilization Technology of Ministry of Education Hebei University of Technology

To study axial/radial profiles of particle velocity in the affected region of an integrated riser outlet, a cold model was developed for the integrated riser reactor combining the gas-solid distributor with the fluidized bed. Constraints, related to the gas-solid distributor and the upper fluidized bed, imposed on the particle flow in the riser outlet region, were investigated experimentally. The experimental results showed that with increasing superficial gas velocity, these constraints have strong influences on particle flow behavior, the particle circulation flux in the riser, and the height of the static bed material of the upper fluidized bed. When the constraints have greater prominence, the axial profile of the cross-sectionally averaged particle velocity in the outlet region initially increases and then decreases, the rate of decrease being proportional to the constraint strength. Along the radial direction of the outlet section, the region where the local particle velocity profile tends to decrease appears near the dimensionless radius r/R = 0.30 initially and then, with increasing constraint strength, gradually extends to the whole section from the inner wall. Based on the experimental data, an empirical model describing the constraint strength was established. The average relative error of the model is within 7.69%.

关键词： Combined fluidized bed Riser Outlet structure Particle velocity Constraint strength

The toxic effect of solubilizing excipients on Tetrahymena thermophila BF_5 growth investigated by microcalorimetry

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Chinese Science Bulletin 2010年第18期55卷 1870-1876页

作者： zhang shaofeng YAN Dan TANG HuiYing YANG Ming WANG YueSheng XIAO XiaoHe China Military Institute of Chinese Materia Medica 302 Military Hospital of China Beijing 100039 China Jiangxi College of Traditional Chinese Medicine Nanchang 330004 China

The toxic effect of different solubilizing excipients on the growth and metabolism of Tetrahymena thermophila BF5(***5) at various concentrations was investigated by *** thermogenic curves of ***5 growth were determined at 28°C,and were evaluated by dynamic *** results indicated that the values of growth rate constant(k),maximum power(P1,P2),peak time(T1,T2) and total quantity of heat(Q) varied for different *** was a good linear relationship between k and concentrations(r>0.95,P<0.01).5% inhibition concentration(IC5) of poloxamer 188,Tween 80,PEG 600,PEG 400 and Tween 20 was 2.18,1.07,1.35,0.58,and 0.045 mg/mL,*** the principal component analysis(PCA),Q,k and P1 could characterize the effect of these excipients on ***5 *** evaluation indicated that compared with the control group,poloxamer 188 had the weakest toxicity and Tween 20 had the strongest toxicity.

关键词：生长速率常数嗜热四膜虫毒性作用辅料聚乙二醇400 微量热抑制浓度 ramp

Value of big data to finance:observations on an internet credit Service Company in China

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Financial Innovation 2015年第1期1卷 259-276页

作者： shaofeng zhang Wei Xiong Wancheng Ni Xin Li Credit Financial Information Service Co. Ltd.Beijing 100089China Institute of Automation Chinese Academy of Sciences95 Zhongguancun E RdBeijing 100190China Department of Information Systems City University of Hong KongKowloon TongHong Kong

Background:his paper presents a case study on 100Credit,an Internet credit service provider in China.100Credit began as an IT company specializing in e-commerce recommendation before getting into the credit rating *** company makes use of Big Data on multiple aspects of individuals’online activities to infer their potential credit ***:Based on 100Credit’s business practices,this paper summarizes four aspects related to the value of Big Data in Internet credit ***:1)value from large data volume that provides access to more borrowers;2)value from prediction correctness in reducing lenders’operational cost;3)value from the variety of services catering to different needs of lenders;and 4)value from information protection to sustain credit service ***:The paper also discusses the opportunities and challenges of Big Databased credit risk analysis,which needs to be improved in future research and practice.

关键词： Big data Credit rating Information economics Value of information Finance

Investigation of ion-atom collision dynamics through imaging techniques

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 755-764页

作者： MA XinWen ZHU XiaoLong LIU HuiPing LI Bin zhang shaofeng CAO ShiPing FENG WenTian XU ShenYue Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Graduate University of Chinese Academy of Sciences Beijing 100049China

The principle and technique details of recoil ion momentum imaging are discussed and summarized. The recoil ion momentum spectroscopy built at the Institute of Modern Physics (Lanzhou) is presented. The first results obtained at the setup are analyzed. For 30 keV He2+ on He collision, it is found that the capture of single electron occurs dominantly into the first excited states, and the related scattering angle results show that the ground state capture occurs at large impact parameters, while the capture into excited states occurs at small impact parameters. The results manifest the collision dynamics for the sub-femto-second process can be studied through the techniques uniquely. Finally, the future possibilities of applications of the recoil ion momentum spectroscopy in other fields are outlined.

关键词： imaging of recoil ion momentum collision dynamics state-selective cross section angular differential cross section

Industrial-scale investigations on effects of tertiary-air declination angle on combustion and steam temperature characteristics in a 350-MW supercritical down-fired boiler

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Frontiers in Energy 2021年第1期15卷 132-142页

作者： Xiaoguang LI Lingyan ZENG Hongye LIU Yao LI Yifu LI Yunlong ZHAO Bo JIAO Minhang SONG shaofeng zhang Zhichao CHEN Zhengqi LI School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Guizhou Wanfeng Electric Power Co. Ltd.Xingyi 562400China Guizhou Xingyi Project Department Huadian United(Beijing)Power Engineering Co.Ltd.Xingyi 562400China

Industrial-scale experiments were conducted to study the effects of tertiary air declination angle(TDA)on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler in China with the multiple-injection and multiple-staging combustion(MIMSC)technology at medium and high *** experimental results indicated that as the TDA increased from 0°to 15°,the overall gas temperature in the lower furnace rose and the symmetry of temperature field was *** ignition distance of the fuel-rich coal/air flow *** near-burner region,the concentration of O2 decreased while the concentrations of CO and NO *** concentration of NO decreased in near-tertiary-air *** carbon in fly ash decreased significantly from 8.40%to 6.45%at a load of 260 *** a TDA of 15°,the ignition distances were the shortest(2.07 m and 1.73 m)at a load of 210 MW and 260 MW,*** main and reheat steam temperatures were the highest(557.2℃ and 559.4℃ at a load of 210 MW,558.4℃ and 560.3℃ at a load of 260 MW).The carbon in fly ash was the lowest(4.83%)at a load of 210 *** changing the TDA from 15°to 25°,the flame kernel was found to move downward and the main and reheat steam temperatures dropped *** change of TDA has little effect on NO_(x) emissions(660–681 mg/m^(3) at 6%O_(2)).In comprehensive consideration of the pulverized coal combustion characteristics and the unit economic performance,an optimal TDA of 15°is recommended.

关键词： supercritical down-fired boiler industrialscale experiment tertiary air declination angle coal combustion steamtemperature

Patterns and Cellular Mechanisms of Arm Regeneration in Adult Starfish Asterias rollestoni Bell

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Journal of Ocean University of China 2011年第3期10卷 255-262页

作者： FAN Tingjun FAN Xianyuan DU Yutang SUN Wenjie zhang shaofeng LI Jiaxin Department of Marine Biology College of Marine Life Sciences Ocean University of China Qingdao 266003 P. R. China

To understand the mechanisms of starfish regeneration, the arms of adult starfish Asterias rollestoni Bell were amputated and their regeneration patterns and cellular mechanisms were *** was found that cells in the outer epidermis and inner parietal peritoneum near the end of the stump began to dedifferentiate 4 d after amputation. The dedifferentiated cells in the outer epidermis proliferated,migrated to the wound site and formed a thickened pre-epidermis which would then re-differentiate gradually into ma-ture *** new parietal peritoneum formed on the coelomic side of wound might be from the curvely elongated parietal peritoneum, resulting from the dedifferentiated and proliferated cells by extension. Afterwards, the proliferated cells made the outer epidermis and inner parietal peritoneum invaginate into the interior dermis and formed blastema-like structures together with induced dedifferentiated dermal cells. Most interestingly, the arm regeneration in A. rollestoni was achieved synchronously by de novo arm-bud formation and growth, and arm-stump elongation. The crucial aspects of arm-bud formation included cell dedifferentiation, proliferation and migration, while those of arm-stump elongation included cell dedifferentiation, proliferation, invagination, and arm-wall-across blastema-like structure formation. The unique pattern and cellular mechanisms of amputated arm regeneration make it easier to understand the rapid regeneration process of adult starfish. This study may lay solid foundations for the research into mo-lecular mechanisms of echinoderm regeneration.

关键词： arm regeneration blastema-like structure adult starfish Asterias rollestoni Bell

PVA纤维体积率对PVA-ECC力学性能的影响

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材料导报 2018年第18期32卷 3266-3270,3275页

作者：祝和意张少峰陕西铁路工程职业技术学院陕西省高性能混凝土工程实验室渭南714099

使用国产基体材料并利用铁尾矿砂细骨料替代天然砂,掺入长度为12mm的PVA纤维,制备铁尾矿砂细骨料PVA纤维水泥基复合材料(PVA-ECC),并通过实验研究了PVA纤维体积率对PVA-ECC性能的影响。实验结果表明:PVA-ECC的工作性能和基本力学性能稳... 详细信息

使用国产基体材料并利用铁尾矿砂细骨料替代天然砂,掺入长度为12mm的PVA纤维,制备铁尾矿砂细骨料PVA纤维水泥基复合材料(PVA-ECC),并通过实验研究了PVA纤维体积率对PVA-ECC性能的影响。实验结果表明:PVA-ECC的工作性能和基本力学性能稳定,制备工艺满足要求。PVA纤维体积率对提高PVA-ECC抗压强度的作用不明显,体积率在1.6%~2%时,PVA-ECC破坏后的整体性较好,体积率为2%时最佳,但过量的PVA纤维掺入会降低其抗压强度。PVA纤维体积率对PVA-ECC韧性的影响显著,体积率在1.6%~2%时,韧性明显增加,体积率为2%时的效果最佳,其极限荷载和抗弯强度达到峰值,弯曲韧性指标显著增大,试件破坏前出现多缝开裂现象,呈现韧性破坏特征;通过韧性指数法判定PVA-ECC为韧性材料。

关键词： PVA纤维水泥基复合材料体积率力学性能

Laser-induced breakdown spectroscopy as a method for millimeter-scale inspection of surface flatness

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Plasma Science and Technology 2024年第9期26卷 148-155页

作者： Jinrui YE Yaju LI Zhao zhang Xinwei WANG Kewei TAO Qiang ZENG Liangwen CHEN Dongbin QIAN shaofeng zhang Lei YANG Xinwen MA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000People’s Republic of China Advanced Energy Science and Technology Guangdong LaboratoryHuizhou 516000People’s Republic of China University of the Chinese Academy of Sciences Beijing 100049People’s Republic of China Key Laboratory of Atomic and Molecular Physics&Functional Materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070People’s Republic of China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

A non-contact method for millimeter-scale inspection of material surface flatness via Laser-Induced Breakdown Spectroscopy(LIBS)is investigated *** experiment is performed using a planished surface of an alloy steel sample to simulate its various flatness,ranging from 0 to 4.4 mm,by adjusting the laser focal plane to the surface distance with a step length of 0.2 *** is found that LIBS measurements are successful in inspecting the flatness differences among these simulated cases,implying that the method investigated here is *** is also found that,for achieving the inspection of surface flatness within such a wide range,when univariate analysis is applied,a piecewise calibration model must be *** is due to the complex dependence of plasma formation conditions on the surface flatness,which inevitably complicates the inspection *** solve the problem,a multivariate analysis with the help of Back-Propagation Neural Network(BPNN)algorithms is applied to further construct the calibration *** detailed analysis of the model performance,we demonstrate that a unified calibration model can be well established based on BPNN algorithms for unambiguous millimeter-scale range inspection of surface flatness with a resolution of about 0.2 mm.

关键词： laser-induced breakdown spectroscopy machine learning surface flatness