Fe-23Cr-15Co-2Mo-0.5Ti永磁合金的SpinodaⅠ分解与磁硬化

用磁性测量、透射电镜、穆斯堡尔效应和磁畴观察（静态与准静态）等方法研究了Fe—23Cr—15Co—2Mo—0.5Ti合金在磁场处理和等级时效过程中的Spinodas分解和磁硬化。实验结果表明,合金的调幅分解是连续地进行的,没有明显的阶段性。分解后显微组织也是不均匀的,从而限制了含金矫顽力的提高。等级时效前,α₁相和α₂相都是铁磁性的,合金是多畴体,合金的矫顽力是畴壁位移决定的,而等级时效后,α₂相区已变成非铁磁性。合金内部存在相互作用畴。但合金的矫顽方是由单畴粒子的磁矩转动来决定。     

浅析燃气企业需求侧管理

在国内燃气市场竞争加剧和能源紧张的形势下,燃气需求侧管理已经成为燃气企业优化负荷结构、提高管网综合效率和争取企业最大盈利空间的主要手段之一,也是燃气企业可持续发展的重要动力和源泉.燃气行业需求侧管理与电力基本相同,但存在着差异.电力行业具有"产、供、销"瞬间平衡的特征,而燃气不仅可以储存,而且储存还是调峰的主要手段.本文通过介绍法国燃气行业需求侧管理,对国内燃气企业需求侧管理进行分析,提出了燃气需求侧管理主要用于确定发展用户的原则,调节市场供需,关注冬夏季峰谷差.通过采取技术、管理和经济措施引导用户降低冬季高峰,填充夏季低谷,提高管网的综合效率的思路.     

异型材拉拔模具设计的变分方法

采用了变分法原理,对异型材拉拔模具设计的方法进行了研究．初步实践表明,拉拔模具设计采用变分的方法可应用计算机进行辅助设计,是简便、易行的方法,已成功地用于梅花轴形件的拉拔模具设计     

药剂在稀土浮选体系中的交互作用与相关关系

用三因素二次回归正交实验研究了Na₂SiO₃,H₂₀₅,H₁₀₂浮选药剂在稀土浮选体系中的交互作用,提出了浮选指标与三者用量的相关数学模型和用等值曲线法讨论Na₂SiO₃,H₂₀₅,H₁₀₂之间的交互作用规律,并进行了实践验证.结果表明,Na₂SiO₃,H₂₀₅,H₁₀₂三者之间存在着强度不同的交互作用,以H₂₀₅与Na₂SiO₃作用最为强烈,H₂₀₅与H₁₀₂次之,Na₂SiO₃与H₁₀₂较弱.该交互作用规律在新宝力格稀土选厂应用收到了较好效果.在精矿品位和回收率与原来相近的情况下,H₁₀₂用量保持原有水平,而Na₂SiO₃和H₂₀₅的用量分别降低了19.46%和39.52%.     

Microstructural evolution of a silicon carbide-carbon coated nanostructured ferritic alloy composite during in-situ Kr ion irradiation at 300℃ 450℃

This work focuses on irradiation behaviors of a novel silicon carbide and carbon coated nanostructured ferritic alloy (SiC-C@NFA) composite for potential applications as a cladding and structural material for next generation nuclear reactors.The SiC-C@NFA samples were irradiated with 1 MeV Kr ions up to 10 dpa at 300 and 450 ℃.Microstructures and defect evolution were studied in-situ at the IVEM-Tandem facility at Argonne National Laboratory.The effects of ion irradiation on various phases such as α-ferrite matrix,(Fe,Cr)7C3,and (Ti,W)C precipitates were evaluated.The α-ferrite matrix showed a continuous increase in dislocation density along with spatial ordering of dislocation loops (or loop strings) at ＞5 dpa.The size of the dislocation loops at 450 ℃ was larger than that at 300 ℃.The nucleation and growth of new (Ti,W)C precipitates in α-ferrite grains were enhanced with the ion dose at 450 ℃.This study provides new insight into the irradiation resistance of the SiC-C@NFA system.     

土木工程预就业人才培养模式探讨

通过预就业人才培养模式的探讨与实践,提高学生的动手能力,增强学生的工程能力,缩短就业距离,提高学生的就业水平,为土木工程专业的实践教学改革摸索一条新的路子。     

Air pollution and meteorological conditions significantly contribute to the worsening of allergic conjunctivitis: a regional 20-city, 5-year study in Northeast China

This study is the first to explore the potential associations among allergic conjunctivitis (AC), air pollution, and meteorological conditions in Northeast Chin...     

Exploratory study of betavoltaic battery using ZnO as the energy converting material

Third-generation-semiconductor zinc oxide is utilized as an energy converting material in a betavoltaic battery, where 0.06 Ci~(63) Ni and 8 Ci~(147) Pm are used as the beta sources. Based on a Monte Carlo simulation, the full scales of the devices are derived as 17 and 118 lm,respectively, for both sources. The influences of semiconductor doping concentrations on the electrical properties of the devices are analyzed. For a typical doping concentration N_A= 10~(17) cm~(-3), N_D= 10~(16) cm~(-3), the conversion efficiencies are 7.177% and 1.658%, respectively, using63 Ni and147 Pm sources. The calculation results of energy deposition in materials for the two sources show that the doping concentrations drop to 1 × 10~(13)–5×10~(14) cm~(-3) and 1 × 10~(12)–5×10~(13), and accordingly, the energy conversion efficiencies rise to 14.212% and 18.359%, respectively.     

面向边缘计算的嵌入式FPGA卷积神经网络构建方法

当前,高计算消耗的应用和服务逐渐从集中式云计算中心向网络边缘的嵌入式环境迁移,FPGA因其灵活性和高能效特性,使其在边缘计算的嵌入式系统中得到广泛的应用.传统的FPGA卷积神经网络构造方法存在设计周期长和优化空间小等缺点,无法有效探索硬件加速器的设计空间,在网络边缘的的嵌入式环境下尤为明显.针对该问题,提出一种面向边缘计算的嵌入式FPGA平台卷积神经网络通用的构建方法.通过设计卷积神经网络函数中的网络层间可复用的加速器核心,以少量硬件资源实现性能优化的卷积神经网络硬件;通过拓展设计、缓存优化及数据流优化等技术,实现HLS设计优化;利用该方法在嵌入式FPGA平台上构建相应卷积神经网络,实验结果表明:优化后的网络模型在与Xeon E5-1620 CPU和GTX Titan GPU相比时,在功耗与性能方面具有一定优势,适合应用于边缘计算环境中.