摘要：Direct carbon solid oxide fuel cells(DC-SOFCs)are promising,green,and efficient power-generating devices that are fueled by solid carbons and comprise all-solid-state *** suitable anode materials for DC-SOFCs is a substantial scientific *** we investigated the use of La_(0.75)Sr_(0.25)Cr_(0.5)Mn_(0.5)O_(3)-δ−Ce_(0.8)Gd_(0.2)O_(1.9)(LSCM−GDC)composite electrodes as anodes for La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3)-δelectrolyte-based DC-SOFCs,with Camellia oleifera shell char as the carbon *** LSCM−GDC-anode DC-SOFC delivered a maximum power density of 221 mW/cm^(2) at 800℃ and it significantly improved to 425 mW/cm^(2) after Ni nanoparticles were introduced into the LSCM−GDC anode through wet *** microstructures of the prepared anodes were characterized,and the stability of the anode in a DC-SOFC and the influence of catalytic activity on open circuit voltage were *** above results indicate that LSCM–GDC anode is promising to be applied in DC-SOFCs.

摘要：The mechanism of oxygen pressure acid leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation was investigated in this *** sphalerite was fabricated with varying amounts of iron content via the sintering of ZnS and FeS and used for the pressure acid leaching *** variations in the potential of the pressure leaching system were investigated by using a self-designed potential *** results showed that compared to the non-iron sphalerite,there was a violent redox reaction between the 25.70%Fe-artificial sphalerite and dissolved oxygen during the process of pressure leaching;and the catalytic mechanism was attributed to the redox couple Fe^3+/Fe^2+,where Fe3+oxidizes the H2S gas film and the reduced Fe2+state is subsequently oxidized by the dissolved ***,the effect of temperature,H2SO4 concentration,and oxygen partial pressure on the artificial sphalerite with different iron contents was *** sphalerite samples with iron content were observed to dissolve more easily in sulfuric acid compared to the non-iron ***,the activation energy of artificial sphalerite was observed to be lower in the sample with 25.70%iron content(22.26 kJ/mol)compared to that with no iron(32.31 kJ/mol);and the apparent reaction orders were obtained with respect to H2SO4 concentration(1.10 and 1.36)and oxygen partial pressure(1.29 and 1.41),respectively.A comprehensive kinetic model was developed on the basis of the experimental data and the fitted leaching ratio plot;and the kinetic equations for the leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation were determined.

摘要：为研究混凝土断裂特性与尺寸效应,引入断裂能和等效应变表示混凝土的损伤演化规律,结合混凝土塑性变形特征,提出基于断裂能的混凝土弹塑性损伤本构模型,并建立相应的数值计算模型。为验证数值计算结果的合理性,引入改进的能量尺寸效应公式进行对比分析。通过对三点弯曲梁的有限元数值模拟和断裂参数敏感性分析发现,尺寸较小的梁失效时,断裂过程区未扩展至特征长度,限制了能量耗散,从而提高了梁的抗断裂能力,增强了梁的名义强度;随着尺寸增大,失效时的断裂过程区逐渐接近特征长度,梁的名义强度逐渐减小;当断裂过程区达到特征长度后,结构名义强度不再随梁尺寸的增大而减小。

摘要：以设计制造金属艺术品鼎为例,将选区激光烧结快速原型技术应用到艺术铸造领域,具有把复杂的艺术品铸件CAD模型直接转化为实体原形的熔模型的特点,实现了金属艺术品无模快速制造,总体精度为100±0.15mm;特别在针对古代青铜器的精确复制方面,解决了传统艺术铸造的金属工艺品产生尺寸收缩的问题。

摘要：消能减震技术能显著提高建筑物的抗震性能,消能器的效果依赖其与主体结构的有效连接,目前关于阻尼器与整体结构有效连接设计方法的研究不多。针对工程中金属阻尼器的中间柱型连接形式,本文提出一种带有预埋件的悬臂墙构造,并给出设计方法及其设计要点。为进一步验证该设计方法的可靠性,探究悬臂墙的受力性能,对两个试件开展拟静力单向加载和低周往复加载试验。研究结果表明,悬臂墙裂缝从预埋件连接处开始发展,最终破坏时墙角及预埋件核心区应力较大,增设暗梁暗柱可较好地提高悬臂墙的承载能力。型钢预埋件配合暗梁暗柱能使悬臂墙在设计尺寸较小的情况下承受较大的设计阻尼力,保证阻尼器充分发挥消能效果。

摘要：以设计制造铜“鼎”艺术品为例,通过构思、创作设计了铜鼎的CAD三维模型;并采用选区激光烧结(SLS)技术,直接烧结出了PS原模;通过渗蜡处理后,得到了强度高和尺寸稳定性好的聚苯乙烯(PS)熔模;并针对含有PS、蜡等有机成分和碳酸钙、石墨等无机填料的蜡模的难熔失问题,提出了合适的PS熔模熔失和型壳焙烧的工艺方案。通过实验表明,焙烧后的型壳内光滑、干净,且强度、致密性均较高;通过浇铸铜合金,成功地制备出了造型复杂、制作精美、尺寸精度高、表面光洁的铜“鼎”艺术品,实现了金属艺术品无模快速制造。

摘要：设计阶段影响堆石坝工程投资预测的主要因素为砂石料的计价方式和上坝砂石料平衡调配方案.针对目前堆石坝工程设计概(估)算的编制主要存在砂石料计价不合理、上坝砂石料平衡调配重视不足、土石坝坝料压实定额的使用不准确及面板接缝止水子目缺项等问题,结合定额和工程实践分析了具体分项工程的砂石料计价方式和上坝砂石料平衡调配方案.在此基础上,根据坝体分区对筑坝材料的要求,提出土石坝坝料压实工序概算定额的合理组合和使用范围.同时根据已建混凝土面板堆石坝接缝止水的基本结构型式和材料的应用与施工情况,对面板接缝止水定额子目进行了修订和补充.

摘要：采用常压浸出与加压浸出相结合的方法,研究硫化锌精矿在富氧硫酸体系中的常压直接浸出动力学。结果表明:锌浸出受界面化学反应控制,浸出反应表观活化能为(44.28±4.28)kJ/mol。浸出槽底部锌的浸出速率远高于浸出槽上部锌的浸出速率,且随槽底矿浆压力的增大,锌的浸出速率明显提高。进一步基于收缩核模型,通过二次回归方法,建立浸出槽底部锌的浸出动力学方程。在硫化锌精矿常压富氧直接浸出中,对于位于浸出槽底部的锌浸出,温度的影响明显大于矿浆压力的影响。

摘要：针对以黝铜矿为主体矿物的复杂硫化铜矿开展热活化-加压浸出工艺研究。结果表明:复杂铜精矿经573K温度热活化1～2h后,在浸出温度453K,氧分压0.6MPa,初始硫酸浓度1.23mol/L,液固比5:1,木质素磺酸钙用量为精矿质量的1.25%等条件下,浸出仅2h就可使铜和锌浸出率分别高达94.08%和96.95%,而铁浸出率仅为22.37%;在复杂铜精矿热活化预处理过程中,未见铅、锌、硫和砷等元素挥发损失,并探讨了复杂铜精矿的热活化机理。

摘要：应用人体艺术克隆技术,通过新型的硅橡胶软模复制手型,制成蜡模,然后采用熔模制壳工艺和石膏型工艺制造出手型金属艺术品。与高分子合成材料的制品相比,金属艺术品具有永不变形、永久收藏,能清晰地展现人的皮肤纹理,极具时尚性、个性和艺术性的特点,满足了大众对个性化金属艺术品收藏的需求。