摘要：First-principles calculations were performed to investigate the structures and energetics of {101n} coherent twin boundaries(CTBs) and glide twin boundaries(GTBs) in hexagonal close-packed(hcp) Ti. The formation mechanism of GTBs and their correlation with twin growth were fundamentally explored. Results suggested that GTBs can form from the gliding of CTBs, through their interaction with basal stacking fault. The gliding eventually restored the CTB structures by forming a pair of single-layer twinning disconnections. The pile-up of twinning disconnections should be responsible for the wide steps at twin boundaries as observed in high-resolution transmission electron microscopy, which can further promote twin growth. Possible effects of various alloying elements on pinning twin boundaries were also evaluated, to guide the strengthening design of Ti alloys.

摘要：采用一性原理计算考察25种合金化元素在大多数商业牌号Al−Cu−Li−Mg合金中主要纳米相(δʹ-Al3Li、θʹ-Al2Cu、T1-Al6Cu4Li3和S-Al2CuMg)之间的溶质配分能和配分行为。计算结果表明,主合金化元素Li不能直接影响θʹ和S相,Cu不能直接影响δʹ相,Mg不能直接影响θʹ和δʹ相,但可以较弱地固溶于T1相。对于微合金化元素,Si是唯一一种可以固溶于4种纳米相的元素。Au能固溶于δʹ、θʹ和S相,Cd能固溶于δʹ、T1和S相,Zr能固溶于δʹ和T1相,Ni仅有微弱的趋势固溶于θʹ和S相。Ti、V、Zn、Ag和Mo只能固溶于δʹ相,而Cr、Mn、Fe和Co对这4种纳米相均没有直接影响。几乎所有的稀土元素均能强烈固溶于T1、δʹ和S相,但无法固溶于θʹ相。仅Sc略显特殊,对S相没有明显的固溶趋势。计算预测的溶质配分能构成了一个原型数据库,有利于指导和加速Al−Li合金及其他相关Al合金的设计。

摘要：为避免张紧器对大直径薄壁海底管道(径厚比D/t≥45)造成椭圆化损伤,须先应用大型有限元软件ABAQUS对张紧器造成的管道椭圆化进行分析,并结合DNV规范确定管道铺设安装期间张紧器的允许最大张紧力。而后应用OFFPIPE软件进行海底管道的安装分析,校核管道应力应变。对于大直径薄壁海底管道,是否考虑管道椭圆化损伤将会影响管道铺设方案的确定。

摘要：在数字孪生技术中,复杂模型和生产逻辑的运行会消耗大量资源,且硬件能力与用户需求存在差异,进而导致模拟精度和实时性难以得到保证,降低系统可用性.为此,提出一种可视化与逻辑运算协同处理的数字孪生制造装备实时同步计算框架.首先,根据车间多维度信息构建设备数字模型,考虑硬件能力和用户个性化计算需求,提出可配置、自适应的系统环境映射方法以修正模拟保真度,确保孪生装备的实时准确运行,并以光照环境映射为例说明其流程;然后,提出基于仿真的六自由度机械手运动逻辑解算算法,将渲染帧时作为仿真时钟推进步长,保证模型运动准确以及可视化与解算同步,并将算法泛化,以应用到其他多体设备中;最后,基于Web设计并开发数字孪生车间建模仿真云平台,以六自由度机械手与某转向架构架加工车间为应用对象对所提方法进行验证.结果表明:随着映射保真度自适应下降,模拟响应速度提升45%,同时GPU和CPU的资源利用率有效降低;证明本文所提方法可实现资源合理配置与系统高效计算,并减少误差累计,是一种高可用的实时协同计算方法.

摘要：本文针对城市轨道交通的特点，结合工程实践，从噪声源分析入手，对轨道交通噪声环境评价内容、评价方法及噪声防治对策进行了探讨。

摘要：在超导线圈性能测试实验中,失超检测系统是探究超导线圈失超特性的主要装置。由于线圈失超时的直流高压会危害整个检测系统的安全性,且实验现场电磁环境复杂,为了确保检测系统的安全可靠运行,设计了一款低功耗且具备信号预处理功能的集成化高压隔离设备。该设备选用delta-sigma(Δ-Σ)调制器作为高压隔离器件并搭配STM32F103主控芯片、MAX292滤波芯片等模拟器件,实现对直流高压的隔离和对输入信号的预处理。设备通过RS485协议与上位机通讯,获取信号调理参数。

摘要：Background Antiviral therapy can lead to regression of fibrosis in chronic hepatitis B(CHB),but it has a limited effect on *** medicines(CMs),particularly Fuzheng Huayu Tablet(扶正化瘀片,FZHY),have an antifibrotic effect in patients with *** To observe the safety and efficacy of adjunctive FZHY in patients with hepatitis B virus(HBV)cirrhosis,this study was designed as a randomized,placebo-controlled,double-blind,parallel assignment,multicenter trial at 20 centers in *** total 700 naive patients will be enrolled with compensate cirrhosis due to HBV,and randomly assigned into 2 groups,receiving entecavir(0.5 mg,daily)and FZHY placebo(1.6 g,3 times a day),or entecavir(0.5 mg,daily)and FZHY(1.6 g,3 times a day),*** primary endpoint was histological improvement at week *** secondary outcome is the decline values of liver fibrosis using the noninvasive methods from baseline to week 48 in each arm of the *** events such as stomach upset,headache,fatigue,dizziness,nausea will be strictly *** Through this study,we hope to generate a solid evidence for the therapeutic strategy of HBV cirrhosis with a combination of anti-viral such as ETV and anti-fibrotic herbal product such as *** version:Version 1.3,Date:*** registration number:NCT02241590.

摘要：Academic circles at home and abroad pay little attention to Rabbit’s work in Mrs. Smith’s garden in Rabbit, *** does Rabbit “has it pretty good” when working in the garden? From the background of economicdemocratization in Western countries, it can be seen that labor relations in the garden have changed, and Rabbit hastaken control of the garden. This article starts with a Chinese translation of Rabbit, Run and explores the changes inRabbit’s working status in the garden due to economic democratization. It also reveals that in the case of gainingcontrol of the garden, Rabbit’s work has been changed in some aspects.

摘要：智能广告创作已成为国内外研究热点,但鲜见对基础性智能广告创作模式研究进展的专题梳理、评析与反思。梳理了智能广告创作模式研究演进脉络:从“消费者导向的‘旧元素新组合’”模式到“具体情境下消费者导向的‘旧元素新组合’”模式,再到“目的与手段统一、具体情境下消费者导向的‘旧元素新组合’”模式及“人机协同、目的与手段统一、具体情境下消费者导向的‘旧元素新组合’”模式,进而,不仅在评析基础上明确了未来研究方向——动态完整的智能广告创作模式,而且立足于广告主的数字营销战略目标,从网络议程设置理论视角,建构了基于消费者品牌知识管理的智能广告创作模式,为学界与业界提出了亟须深入解决的问题。

摘要：可得然胶,作为一种微生物胞外多糖,因其在食品体系中良好的凝胶性、持水性、增稠性及冻融稳定性等特性,被广泛用作食品添加剂。近年来,针对可得然胶与生物大分子间相互作用的调控研究,已成为食品科学领域的研究热点,旨在优化食品质地、增强稳定性及推动新型健康食品的开发。然而,目前对于可得然胶与生物大分子相互作用及其调控机制的系统性总结尚不充分。鉴于此,本文对近年来该领域的研究进展进行全面的归纳总结,特别聚焦于可得然胶与食品中的多糖、蛋白质等大分子之间的相互作用及其应用,旨在为新型功能食品的精准设计与创新开发提供理论基础。