Influence of tool rotation speeds on mechanical and morphological properties of friction stir processed nano hybrid composite of MWCNT-Graphene-AZ31 magnesium

The ever-increasing demand for light weighted hard materials for transportation industries encouraged researchers to develop composites with excellent mechanical properties which can transform it into more economical and eco-friendly.Reinforcing the metals with carbonaceous nanomaterials are progressively in focus due to their excellent capability to inculcate and tailor the properties of MMCs.In the present research,a hybrid nanocomposite of MWCNT-Graphene-AZ31 Mg alloy has been developed by using variable tool rotation speeds with friction stir processing(FSP).Optimized reinforcement ratio of 1.6%vol.MWCNT and 0.3%vol.of graphene have been used with variable tool rotation speeds,whereas other processing parameters are kept constant.The developed specimens were investigated using standard testing equipment for evaluating and comparing the mechanical properties on the basis of the microstructure of the processing regions and their morphological analysis,according to the ASTM standards.The obtained results revealed an improvement of 19.72%in microhardness and 77.5% of compressive strength in comparison with the base metal AZ 31 Magnesium alloy,with a tool rotational speed of 1400rpm.The values of tensile stress and percentage area reduction were recorded as less than that of the base metal matrix,but an increasing trend has been observed in the values of both with the improvement on rotational speeds of the tool.The effectual strengthening mechanisms are analyzed on the bases of SEM images and observed that discussed and found that grain refinement strengthening is the major contributor to the strength of the nanocomposite.

THE ANALYSIS OF COMPATIBLE SYSTEM OF AMTI AND SAR

Based on the analysis of Adaptive Moving Target Indication(AMTI) and the signal processing of Synthetic Aperture Radar(SAR), a complete compatible system of AMTI and SAR is put forward. The compatibility and effectiveness of this system is prcved in theory. The results of simulation show that this system not only has good ability in stationary targets imaging but also has ability in detecting moving targets under the background of strong clutter.

Preparation and properties of Ce_(0.8)Ca_(0.2)O_(1.8) anode material by glycine-nitrate process

Ce0.8Ca0.2O1.8 (CDC82) anode material was prepared by glycine-nitrate process(GNP). Thermogravimetric(TG) analysis and differential scanning calorimetric(DSC) methods were adopted to characterize the reaction process of CDC82 material. X-ray diffractometry(XRD), scanning electron microcopy(SEM), direct current four probe (four-probe DC) and temperature process reduce(TPR) techniques were adopted to characterize the properties of CDC82 material. After the precursor was sintered at 750 ℃ for 4 h, CDC82 material with pure-fluorite structure and nanometer size was obtained. The total conductivity of CDC82 changes little with temperature in air at 50?850 ℃ , and the maximum value is 0.04 S/cm at 750 ℃ . The total conductivity wholly becomes larger when the atmosphere changes from air to hydrogen, which greatly increases with increasing temperature and reaches the maximum value of 1.09 S/cm at 850 ℃. Some impurities such as CeMg and La2O3 exist after the mixture of CDC82 anode and La1?xSrxGa1?yMgyO3?δ (LSGM) electrolyte material is sintered at 1 200 ℃ for 15 h. The CDC82 material as anode material has excellent catalytic property for hydrogen and methane.

On consistency of the weighted arithmetical mean complex judgement matrix

The weighted arithmetical mean complex judgement matrix （WAMCJM） is the most common method for aggregating group opinions, but it has a shortcoming, namely the WAMCJM of the perfectly consistent judgement matrices given by experts canot guarantee its perfect consistency. An upper bound of the WAMCJM＇s consistency is presented. Simultaneously, a compatibility index of judging the aggregating extent of group opinions is also introduced. The WAMCJM is of acceptable consistency and is proved provided the compatibilities of all judgement matrices given by experts are smaller than the threshold value of acceptable consistency. These conclusions are important to group decision making.

A Study of the Replacement of Materials in Smart Card

Gold, nickel and copper are usually used in connector of the smart card. Since Au is expensive and Ni is an allergenic material, simulated (CES) and bibliographical work is carried out in order to replace the Au and Ni layer in smart card connectors without sacrificing reliability. During the work, mechanical and electrical properties, corrosion resistance, cost, toxicity and process compatibility of the samples have been taken into consideration. Cu alloying with Zn or Sn, Cr and stainless steel were selected for electrodeposition process. Secondly, carbides (WC, TiC, ZrC), Ti, TiN, borides (TiB2) and silicide (MoSi2) are considered as a vapour deposited materials and some Cu alloying with Al, N or Mg also considered via ion implantation processes. But, vapour deposition and implantation are high energy processes compared to the electrodeposition process, which is expensive. Therefore, electrodeposited materials such as, Cu alloys (Brass or bronze), Cr and stainless steel could be considered as promising candidate to replace the Au and Ni layer in smart card connectors.

Research on the Influencing Factors of Purchasing Internet Financial Wealth Management Products Based on AHP

Internet financial wealth management product(IFWMP)has recently been one of the most gained popularity.There are limited quantitative research on IFWMP which can help customers to choose products based on the significance of each factor.In this paper,a multi-criteria decision-making model for IFWMP was developed,namely the analytic hierarchy process(AHP)which is commonly used to make decisions for unstructured problems through quantifying weights of each criterion.This paper investigated ten influential factors relevant to the purchase of IFWMP and analyzed the frequency of collected response to show the significance of the factors.Based on the quantified weights,the results of the research indicated that compatibility,product liquidity,perceived ease of use,and perceived usefulness affected investors purchasing behaviors and that every investor should pay great attention to.

Research on the Influencing Factors of Purchasing Internet Financial Wealth Management Products based on AHP

Internet financial wealth management product(IFWMP)has recently been one of the most popularity.There is limited quantitative research on IFWMP which can helps customers to choose the products based on the significance of each factor.In the paper,a multi-criteria decision-making model of IFWMP was developed,namely analytic hierarchy process(AHP)which is used to make decisions to the unstructured problems through quantifying weights of each criterion.This paper investigated ten influential factors relevant to the purchase of IFWMP and analyzed the frequency of collected responds to show the significance of factors.Based on the quantified weights,the result of the research indicated that compatibility,product liquidity,perceived ease of use and perceived usefulness affect the investors purchasing behaviors most that every investors should pay great attention to.

SZS-702H测井仪磁定位信号处理电路改进研究

随着套管开窗侧钻井的增多,测井仪器外径要求越来越小,使得测井仪器供电及信号传输方式需要采用单芯电缆传输方式来完成,同时对下井仪器的各项技术指标也提出更高的要求。本文针对SZS-702H测井仪器在使用中出现的磁定位曲线干扰和磁定位信号丢失等现象,提出改进措施,标准井试验与生产应用效果良好,具备良好的推广前景。

俄罗斯液体潜射弹道导弹长期贮存材料工艺技术

对液体潜射弹道导弹长期加注贮存技术的发展进程、最新进展及研究现状进行概述。重点介绍俄罗斯液体潜射弹道导弹的结构设计、材料选取和制造工艺以及出厂加注封装和密封性检测方法,最后指出实现长期加注贮存的技术路径。

何首乌肝损伤机制及减毒方法研究进展

何首乌Polygonum multiforum Thunb.是临床常用滋补中药,同时作为一种保健中药在药膳和食膳中广泛应用,但是近年来由于不时出现何首乌及其制品致肝损伤的报道,引起了研究者的警觉及关注。本文通过整理分析关于何首乌致肝损伤的国内外临床相关报道,从何首乌致肝毒性的物质基础二苯乙烯苷类、蒽醌类化合物和没食子酸等成分及其潜在肝毒性机制(包括代谢酶改变、氧化应激、炎症反应、线粒体损伤、肝细胞异常凋亡等方面)进行归纳总结,探讨炮制减毒和配伍减毒两种减毒方法对何首乌肝毒性的影响和机制。

补骨脂肝毒性及其减毒方法的研究进展

补骨脂因含香豆素类、黄酮类和单萜酚类等化学成分,具有抗肿瘤、抗氧化、抗菌、抗炎、调节雌激素水平、促进骨生长、神经保护等作用而广泛用于肾部疾病、脾胃病、肢体经络病、妇科病的治疗,是临床常用的传统“无毒”的补益类中药,但近年来,国家药品不良反应监测中心多次通报警示补骨脂相关制剂(如壮骨关节丸、仙灵骨葆胶囊、致康胶囊)引发的肝损伤问题,更有单味补骨脂引发肝损伤的临床病例报道,其肝损伤现象已成为当前行业研究的热点及难点,为补骨脂的临床安全用药带来极大挑战。课题组前期基于脂多糖模型证实了补骨脂具有特异质肝损伤的属性,并从体内外角度相互验证了补骨脂甲素、补骨脂乙素、补骨脂酚、补骨脂定或可通过调控PI3K-Akt信号通路、NF-κB信号通路、NLRP3信号通路等引发肝损伤。通过对近年来补骨脂肝毒性的相关文献进行整理、归纳,探讨引起补骨脂肝毒性的主要毒理机制,并总结了配伍减毒和炮制减毒对减轻补骨脂肝毒性的重要意义,为补骨脂的临床安全用药提供数据支撑。

青皮的炮制历史沿革、效应物质及古今临方配伍研究进展

青皮为我国传统中药材,炮制历史悠久,方法多样。但随着历史的演变,一些独具特色的炮制方法逐渐消失,我们对青皮不同炮制品种的认识和传承有待加强。同时,各地对不同品种的制法各异,差别较大。而其加工炮制、质量控制、临床使用都不可避免地会受到这些问题的影响和制约。因此,本文通过对青皮炮制历史沿革、现代炮制规范的详细梳理,并综合药理作用的研究进展,强化对青皮及其炮制品优势特色的认识,寻找目前研究与开发的不足之处,为今后优化青皮炮制工艺和建立质量标准控制体系提供参考。此外,从中药功效和临床应用的角度进一步挖掘青皮及其炮制品在复方配伍方面的特点与规律,促进对现代药理活性及潜在机制的阐述,也为现代配伍研究提供依据。

基于蒙医药学古籍文献探析蒙药药物警戒科学内涵

目的从药物警戒角度对蒙医药学古籍文献进行研究,阐释蒙药药物警戒理论内涵,为深入开展蒙药安全性评价与蒙药药物警戒研究提供参考。方法通过梳理4世纪以来40余本蒙医药学经典著作及史籍文献,挖掘其中蕴含的药物警戒内容,分析蒙医药学毒性理论及安全合理用药特点。结果蒙医药学重视药物两重性,即药物在治疗疾病的同时也会给人体带来危害。蒙药药物警戒主要体现在毒的认识,中毒解毒,饮食禁忌、起居禁忌、体质禁忌、疾病禁忌等用药禁忌,配伍、炮制等减毒方法,药物剂量、疗程的控制原则及剂型特点等方面。结论蒙古族对“毒”的认识和使用历史悠久,加之蒙医药学理论特点和临床用药区别,安全合理用药实践内容丰富且独具特色。挖掘蒙药药物警戒科学内涵,对指导现代临床合理使用蒙药和传承传统医药学都具有现实和深远意义。

In-vitro biomineralization and biocompatibility of friction stir additively manufactured AZ31B magnesium alloy-hydroxyapatite composites

The present study aims to evaluate effect of hydroxyapatite(HA,Ca10(PO4)6OH2),a ceramic similar to natural bone,into AZ31B Mg alloy matrix on biomineralization and biocompatibility.The novel friction stir processing additive manufacturing route was employed to fabricate Mg-HA composites.Various HA contents(5,10,20 wt%)were incorporated into Mg matrix.Microstructural observation and chemical composition analysis revealed that refined Mg grains and dispersion of HA particles at micro/nanoscales were achieved in Mg-HA composites after the friction stir processing.The biomineralization evaluation were carried out using immersion experiments in simulated body fluid followed by mineral morphology observation and chemical composition analysis.The wettability measurements were conducted to correlate the biomineralization behavior.The results showed improvement in wettability and bone-like Ca/P ratio in apatite deposit on the composites compared to as-received Mg.In addition,the increase of blood compatibility,cell viability and spreading were found in the higher HA content composites,indicating the improved biocompatibility.Therefore,friction stir processed Mg-20 wt%HA composite exhibited the highest wettability and better cell adhesion among other composites due to the effect of increased HA content within Mg matrix.

附子药理作用机制及减毒增效技术的研究进展

附子具有回阳救逆、补火助阳、温经散寒等功效,但对心脏、肝脏等多系统具有毒性作用,如何在保证疗效的同时降低毒性值得探究。目前,对附子的药理研究主要集中在其强心、保护血管、抗肿瘤、抗炎镇痛及保护神经系统等方面,并在不断挖掘新的方向,如调节免疫及改善糖尿病等。作用机制主要为通过多成分、多靶点、多途径地调控相关信号通路、离子通道等,在生物体内发生细胞水平、组织水平和系统水平的改善。对附子的减毒增效的研究主要是在炮制方法的革新和药物配伍的作用机制等方面。随着科技发展,无胆炮制、微生物发酵技术等逐渐推广应用,不仅能在降低附子毒性的同时维持甚至提升附子的药理作用,还研发出某些疾病的专属性炮制品,对附子的毒理及配伍后药物成分研究也有了长足发展。本文对附子近年来的药理作用及减毒增效的研究进展进行综述,并总结阐述了现有研究的不足之处,以期更好地利用附子资源。

Spheripol装置聚丙烯汽车料产品气味控制

通过优选长效催化剂、调整环管反应器工艺控制参数,降低聚丙烯产品中金属和低分子量聚合物含量;控制气蒸单元、干燥单元操作参数,减少烃类物质和水分残留;优选造粒助剂,控制挤压造粒机操作参数,抑制聚丙烯降解,降低聚丙烯车用料产品气味。聚丙烯车用料产品经过持续改进,气味等级由3.5~4.0降低至2.5~3.0,达到客户使用要求。

配伍比例及炮制方法对川楝子-小茴香药对中9种成分含量的影响

目的考察不同配伍比例及炮制方法对川楝子-小茴香药对中芦丁、异槲皮素、阿魏酸、槲皮素、异川楝素、山柰酚、川楝素、α-蒎烯、反式茴香脑含量的影响,探讨其配伍使用的最优比例。方法分析采用HPLC-DAD法,ZORBAX SB C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相乙腈-0.1%磷酸,梯度洗脱;柱温30℃;体积流量1.0 mL/min;DAD检测器。采用SPSS 24.0软件分析数据之间的差异性。结果9种成分在各自范围内线性关系良好(r≥0.9991),平均加样回收率96.19%~103.13%,RSD 1.86%~2.67%。川楝子-小茴香1∶1、1∶2、2∶1组中9种成分总含量高于川楝子+小茴香(1∶0+0∶1)组(P<0.05),川楝素-小茴香(1∶1)组总含量最高;炮制后,川楝素、异川楝素、α-蒎烯、反式茴香脑含量降低(P<0.05,P<0.01),异槲皮素含量升高(P<0.01),其余成分含量变化不明显。结论该方法准确度高,重复性好,川楝子与小茴香配伍后有利于9种成分总量的溶出,比例为1∶1时含量最高。

论个人信息保护“目的限定原则”的兼容性标准

[目的/意义]我国《个人信息保护法》第六条确立了个人信息处理行为的目的限定原则,规定信息处理者的处理行为须与初始收集目的间具有直接关联。然而,严格的直接关联性标准过度强调个人对信息的支配与控制,难以因应大数据时代下信息流通利用的现实需求,亦无法在法律实效层面真正实现对个人合法信息权益的有效保护。因此,确有必要对目的限定原则的适用标准进行优化。[方法/过程]通过参考借鉴欧盟立法中的兼容性标准与最新发展,归纳构建以关联性评估要素与风险性评估要素为内核,公法关系与私法关系差序适用的本土化兼容性标准。[结果/结论]目的限定原则采取兼容性标准能够合理放宽目的限制的程度,为信息处理行为预留柔性缓冲空间,平衡个人信息的流通与保护。

有毒乌头类中药炮制与配伍减毒机制的研究进展

乌头类中药在我国的药用历史悠久,主要包括草乌、川乌与附子,涵盖诸多生物活性物质。此类中药的中毒剂量与治疗剂量相近,临床治疗窗较窄,在使用时常有中毒事件与不良反应的发生,因此制约其广泛运用。深入探究有毒乌头类中药炮制以及配伍对乌头急性毒性的影响和作用,分析其毒性产生的相关机制,对合理开发乌头类新型制剂、提高乌头类中药的使用安全性有着积极意义,有助于为乌头类中药的合理使用提供有效指导。本文围绕有毒乌头类中药炮制与配伍减毒机制的研究进展予以综述。

基于MATLAB建模的电磁兼容测试中接收机数字化设计

随着虚拟仪器的快速发展,对如何将虚拟仪器的可定制性、易扩展、价格低廉等优势应用于电磁兼容测试的接收机进行了研究。通过让数字化虚拟仪器部分取代乃至完全取代传统仪器,已成为日后电磁兼容技术革新的关注焦点。基于MATLAB软件搭建了接收机的模型,实现了接收机的数字化设计。其中中频滤波器的滤波窗函数采用高斯函数,带宽通过修正系数拟合;检波器经过傅里叶变换,实现信号的频谱计算以及包络线绘制。模型通过频选信号的变化,能够实现峰值和平均值两种检波效果。实际测试结果与模型仿真结果误差小于10%,符合企业测试要求。该模型具有较强的扩展性与兼容性,能对整车与高低压零部件的电磁兼容问题进行一定的监测,设计经验对后续电磁兼容测试过程整体数字化发展有着重要意义。