On mechanical properties of metallic glass and its liquid vitrification characteristics

A systematic survey of the available data such as elastic constants, density, molar mass, and glass transition temperature of 45 metallic glasses is conducted. It is found that a critical strain controlling the onset of plastic deformation is material-independent. However, the correlation between elastic constants of solid glass and vitrification characteristics of its liquid does not follow a simple linear relation, and a characteristic volume, viz. molar volume, maybe relating to the characteristic size of a shear transformation zone (STZ), should be involved

Formation Mechanism Of Lamellar Chips During Machining Of Bulk Metallic Glass

The uniqThe unique lamellar chips formed in turning–machining of a Vit 1 bulk metallic glass (BMG) are found to be due to repeated shearband formation in the primary shear zone (PSZ). A coupled thermomechanical orthogonal cutting model, taking into account force, free volume and energy balance in the PSZ, is developed to quantitatively characterize lamellar chip formation. Its onset criterion is revealed through a linear perturbation analysis. Lamellar chip formation is understood as a self-sustained limit-cycle phenomenon: there is autonomous feedback in stress, free volume and temperature in the PSZ. The underlying mechanism is the symmetry breaking of free volume flow and source, rather than thermal instability. These results are fundamentally useful for machining BMGs and even for understanding the physical nature of inhomogeneous flow in BMGs.ue lamellar chips formed in turning–machining of a Vit 1 bulk metallic glass (BMG) are found to be due to repeated shearband

水泥基材料抗压强度与交流阻抗参数的关系研究

研究了标准养护条件下不同W/B（水胶比）水泥浆体的7 d和28 d抗压强度和交流阻抗响应,并对阻抗谱进行了解析。结果表明水泥浆体的强度随W/B的增大而减小,且呈良好的线性关系。不同W/B的水泥浆体试件的RCCP、RDP、Cmat和CDP与W/B均成良好的幂函数关系。采用RCCP和RDP表征的水泥浆体试件非连通孔和连通孔所占比例基本相同。且同一龄期不同W/B的水泥浆体抗压强度与各阻抗参数也有良好的幂函数关系。因此,可望采用交流阻抗参数预测不同W/B的水泥浆体抗压强度,从而为水泥浆体强度预测提供一种新的方法。福建省杰出青年基金(2015J06012);;\n博士后基金(2017M612140);;\n厦门市科技计划项目(3502Z20183001);;\n福建省石墨烯技术研发项目(闽发改高技〔2017〕105号);;\n福建省自然科学基金(2016J01257

Dynamic Fracture Instability Of Tough Bulk Metallic Glass

We report the observations of a clear fractographic evolution from vein pattern, dimple structure, and then to periodic corrugation structure, followed by microbranching pattern, along the crack propagation direction in the dynamic fracture of a tough Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vit.1) bulk metallic glass (BMGs) under high-velocity plate impact. A model based on fracture surface energy dissipation and void growth is proposed to characterize this fracture pattern transition. We find that once the dynamic crack propagation velocity reaches a critical fraction of Rayleigh wave speed, the crack instability occurs; hence, crack microbranching goes ahead. Furthermore, the correlation between the critical velocity of amorphous materials and their intrinsic strength such as Young's modulus is uncovered. The results may shed new insight into dynamic fracture instability for BMGs. (C) 2008 American Institute of Physics

中国邻近边缘海碳通量研究现状与展望

集成分析了南海、东黄渤海等中国邻近边缘海（简称中国边缘海）海-气界面CO2通量及其所表征的CO2源汇格局,简析海-气CO2通量的主要控制因素;总结了河-海界面、边缘海与大洋的交换界面及输出真光层的碳通量,进而初步构架了简化的中国边缘海碳收支;并与世界其他陆架边缘海碳的源汇格局和通量作了比对,最后对边缘海碳循环研究进行了展望.从周年尺度上看,中国边缘海是大气CO2的源,全年向大气的释放量为（9.5±53）Tg C;河流经过河口输送至中国边缘海的总碳量为（59.6±6.4）Tg Ca-1;中国境内河口释放CO2的总量为（0.74±0.02）Tg Ca-1;西太平洋每年输入中国边缘海的总碳量为2.5Pg Ca-1,可见,西北太平洋输入中国边缘海的碳通量巨大.中国边缘海上层海洋颗粒有机碳输出通量为（240±80）Tg Ca-1.国家自然科学基金项目(批准号:91328202、91428308);;科技部重大科学研究计划项目(编号:2015CB954001);;国家海洋局海洋公益项目(编号:201505003-3);;全球变化专项项目(编号:GASI-03-01-02-02)资

Flooding Efficiency of Flooding systems and Wettability Study on the Simulaitn Rock Surface

为了研究驱油体系在模拟岩芯表面的润湿性，为微重力应用研究提供依据，选择胜利纯梁采油厂c6—41井原油，应用正交实验设计，通过最低瞬时界面张力测定，筛选出阴离子表面活性剂sDc—V、非离子表面活性剂FBB、HPAM和复碱的驱油体系配方．开展室内模拟驱油实验，同时测定驱油体系溶液对模拟岩芯的接触角，并且关联驱油效率和接触角之间的关系，发现驱油效率越高，接触角值越小

Study on the free radical scavenging activity of polyphenolic compounds by on-line high-flux screening method

目的:构建植物化学物在线清除自由基活性高通量筛选技术,创建植物化学物抗氧化活性研究新方法。方法:以附带2个检测器的高效液相色谱(HPlC)装置和流动注射技术为手段,引入二苯基三硝基苯肼(dPPH)有机自由基分别与经HPlC分离的植物化学物发生在线清除反应,优化流速、反应管尺寸等条件,比较反应前后dPPH吸收信号的变化。结果:确定和验证了两类植物多酚化学物茶多酚和丹酚酸在线清除自由基活性HPlC-dPPH表征方法。反应环聚醚醚酮(PEEk)盘管规格为长10M、内径0.254MM,dPPH·浓度为1.0x10-5MOl/l,流速为0.7~0.8Ml/MIn。结论:HPlC-dPPH流动注射在线表征技术能够实现对多组分植物化学物抗氧化能力的高通量筛选。Objective:To construct a high-flux screening procedure by on-line free radical scavenging activity method of phyto- chemicals, and create a new evaluation system of antioxidant activity of natural plant materials.Methods:A HPLC system with two detectors and flow injection techniques was employed.An organic free radicals DPPH was induced on-line HPLC-DPPH and reaction with the single phytochemical components isolated by HPLC.To optimize reactive conditions including flow rate and the size of reaction coil, and detect the DPPH signals before and after reaction.Results:A new on-line HPLC-DPPH method was established for a high-flux screening of several free radical scavenging components exampled as Tea polyphenols and Salvianolic acids.The reaction coil of PEEK was 10 m length and inner diameter 0.254 mm, the concentration and flow velocity of DPPH was 1.0 × 10-5mol/L and 0.7～0.8 ml/ min, respectively.Conclusion:The PHLC-DPPH flow injection hyphenated technique could realize high-flux screening analysis for antioxidant of phytochemicals.江苏省高校自然科学研究计划资助项目(05KJB330083

电化学原位扫描显微红外反射光谱及其对铂表面CO吸附的红外成象

利用fOurIEr变换红外光谱仪 ,红外显微镜和X y扫描平台 ,通过设计和研制原位红外显微池和计算机接口及控制软件 ,建立了电化学原位扫描显微红外反射光谱 .研究工作显示 ,这一新的空间分辨原位红外反射光谱技术不仅可以获得固 /液界面环境中表面微区振动光谱的信息 ,还可以用于电极表面红外成象 .获得的CO在PT多晶电极表面吸附性能的化学图象在 10 -2 CM尺度上给出电极表面微区反应性能的不均一性及其分布 .国家杰出青年科学基金资助项目!(批准号:29525307

基于LTE230潍坊电力无线专网设计与实现

本文针对潍坊通信状况复杂、经费少等现状,结合智能电网配用电通信需求,通过建设LTE230系统,列举了LTE230系统的关键技术。着重分析它在用户信息采集中的应用效果,对比传统的通信网络,具有良好的覆盖效果和传输能力,为LTE230系统的广泛应用提供了良好的示范作用。潍坊科技项目（编号：5206041400TP

五倍子废渣对小麦生长和产量的影响及施肥对其的缓解效应

【目的】研究五倍子废渣对小麦生长及产量的影响,并分析施肥对此影响的缓解效应,为寻求生物质加工剩余物(生物质工业废渣)的环境友好型循环利用方式提供参考。【方法】采用盆栽试验,设置0(CK),10,20,30,40,50,60g/盆7个废渣添加水平,研究在土壤中添加五倍子废渣对小麦形态指标(株高、地径)、抗氧化酶系统(过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT))、渗透调节物质、产量及其构成因素的影响,分析施肥的缓解效应。【结果】不同添加量五倍子废渣对小麦的生长表现出不同程度的抑制作用。随着废渣分解时间的延长,各处理小麦形态指标的差异性逐渐明显。随着废渣添加量的增加,小麦生长受到的抑制效应逐渐增强。随着废渣分解时间的延长,各处理CAT和SOD活性均呈先升高后降低的趋势,而POD活性则呈逐渐降低的趋势;且高剂量处理的抑制程度强于低剂量处理。随着废渣分解时间的延长,可溶性蛋白含量随着废渣添加量的增加呈下降趋势,而可溶性糖含量则呈上升趋势;到播种后88d时,各处理含量逐渐恢复至正常水平。低剂量废渣处理对小麦产量表现为促进作用,但随着废渣添加量的增加,其抑制作用逐渐增强,小麦的产量构成指标逐渐降低。施肥处理可一定程度缓解五倍子废渣对小麦生长和产量的影响。【结论】采用施肥的形式,在种植小麦的农田中添加不超过5 240kg/hm~2的五倍子废渣,对小麦生长不会产生明显的抑制作用,且废渣分解后还可发挥有机肥功能,一定程度上可实现\"生态友好型\"还田的目的。四川省“十三五”农作物育种攻关项目(2016NZ0098-10);;四川省教育厅重点项目(13ZA0246