The Cement Solidification of Municipal Solid Waste Incineration Fly Ash

The chemical composition, the content and the leachability of heavy metals in municipal solid waste incineration （ MSWI） fly ash were tested and analyzed. It is shown that the leachability of Pb and Cr exceeds the leaching toxicity standard, and so the MSWI fly ash is considered as hazardous waste and must be solidifled. The effect of solidifying the MSWI fly ash by cement was studied, and it is indicated that the heavy metals can be well immobilized if the mass fraction of the fly ash is appropriate. The heavy metals were immobilized within cement hydration products through either physical fixation, substhtaion, deposition or adsorption mechanisms.     

聚氮硅烷催化裂解原位合成碳纳米管增强SiC/Si_3N_4复相陶瓷

以聚氮硅烷为前驱体,通过催化裂解原位生成SiC/Si3N4复相陶瓷,同时原位生成碳纳米管增韧相;研究热解温度、掺杂催化剂种类对SiC/Si3N4复相陶瓷微观结构及形态的影响,运用扫描电镜、高分辨率透射电镜、X射线衍射、综合热分析进行结构分析和表征。结果表明,催化裂解可有效增强陶瓷基体的强度和实现基体与纳米相的复合和分散,并降低SiC/Si3N4复相陶瓷晶化温度。     

修武盆地下寒武统页岩气富集条件及有利区预测

利用野外地质调查、岩心观察、测试分析、含气量现场解析等方法,研究修武盆地下寒武统海相富有机质泥页岩分布特征、有机质类型、丰度和成熟度、岩石储集特征及含气量等页岩气成藏条件.结果表明:下寒武统王音铺组、观音堂组黑色泥页岩具有厚度大、分布广、有机碳质量分数高、成熟度高等特点,泥页岩脆性矿物质量分数较高(大于40%),微裂缝、微孔隙发育,具有良好的页岩气形成与富集条件.结合岩样等温吸附实验结果和调查井岩心现场含气量解析数据,采用概率体积法估算修武盆地下寒武统页岩气资源量为2 922.98×108 m3.修水—武宁向斜东部王音铺组泥页岩厚度大于100m,TOC质量分数大于6%,镜质体反射率在2%~3%之间,埋深为1 000~3 000m,构造形态完整,断裂不发育,有利于页岩气的聚集和保存,是区内页岩气勘探有利区域.     

互联网之光张弦梁-悬链梁杂交结构施工关键技术

乌镇世界互联网大会主展馆采用屋脊张弦梁-悬链梁杂交结构体系,形成90 m×200 m的全无柱空间.为了实现整个展馆的快速建造,整个展馆项目运用了动态模块化系统和全预制装配的逻辑.上层建筑结构设置了大量预应力索,形式新颖、受力复杂、施工难度大.为此,对主展馆钢结构施工过程中的关键技术进行了研究,主要包括柔性大跨悬链梁循环...     

四川盆地及其周缘上奥陶统—下志留统页岩气成藏体系研究

通过对页岩层系发育的时代、沉积特征、演化历史、现今所处的大地构造位置、构造特征、页岩残留状况、分布特征、埋深和含气量等因素的综合考虑,根据"单源一位"页岩气成藏体系划分的一般性原则,将四川盆地及其周缘上奥陶统-下志留统页岩气成藏体系划分为川南-川东南、黔北、渝东、湘鄂西、龙门山、米仓山-大巴山和川中7个成藏体系,描述了不同成藏体系中页岩层系的厚度、有机碳含量、成熟度和含气量等特征,并按战略展开区、战略突破区、战略准备区和战略远景区4个层次对成藏体系进行了评价,明确了勘探层次.     

基于双层解耦策略和注意力机制的遮挡目标分割

遮挡目标分割是实例分割中的一个难点,但在多个应用领域有很强的实用价值,例如物流传输线上堆叠快递包裹的分割。针对快递包裹目标遮挡导致难以分割的问题,该文提出一种基于双层解耦策略和注意力机制的遮挡目标分割方法。该方法首先利用带有特征金字塔(FPN)的主干网络提取图像特征;然后,利用双层解耦检测头自动预测实例的重心是否被遮挡并使用不同的分支对两类不同遮挡类型的实例进行检测;接下来,利用注意力改进模块得到无遮挡实例的预测掩模并将这些掩模合成为一个注意力权重图;最后,注意力改进模块利用该注意力权重图帮助有遮挡实例得到分割结果。该研究采集了一个遮挡快递包裹实例分割数据集,并在该数据集上进行实验。实验结果表明,该方法的平均精度(AP)、召回率(Recall)和漏检率(MR^–2)指标分别达到了95.66%, 97.17%和11.78%,较其他方法具有更优的分割性能。     

Multilayer doped-GeSe OTS selector for improved endurance and threshold voltage stability

Selector devices are indispensable components of large-scale memristor array systems. The thereinto, ovonic threshold switching (OTS) selector is one of the most suitable candidates for selector devices, owing to its high selectivity and scalability. However, OTS selectors suffer from poor endurance and stability which are persistent tricky problems for application. Here, we report on a multilayer OTS selector based on simple GeSe and doped-GeSe. The experimental results show improving selector performed extraordinary endurance up to 10¹⁰ and the fluctuation of threshold voltage is 2.5%. The reason for the improvement may lie in more interface states which strengthen the interaction among individual layers. These developments pave the way towards tuning a new class of OTS materials engineering, ensuring improvement of electrical performance.     

Controlled structure preparation of low thermal conductivity Bi4B2O9 foams

In this contribution, Bi₄B₂O₉ foam ceramics with porosity of 76.6%–85.8% and thermal conductivity of .062–.092(W/(m·K)) were successfully prepared for the first time by the foam casting method using bismuth oxide and boric acid as the main raw materials and gelatin as the gel forming agent. The effects of additive content and solid loading on the slurry, pore size, and distribution as well as mechanical and thermal properties of porous ceramics were investigated. The addition of gelatin led to the stable arrangement of the liquid-gas interface, which eventually resulted in a foam with a stable pore structure. The sintered ceramics have a highly spherical morphology with typical micropores and cell window, which may also contribute to the low thermal conductivity of Bi₄B₂O₉ foams. Bi₄B₂O₉ foam with tailored properties and graded pore structure by adjusting the process parameters can be used as a high-performance nuclear reactor insulation material.     

Pd/C embedded crosslinked polystyrene fibers as an efficient catalyst for Heck reactions

Pd/C embedded polystyrene fibers were successfully prepared by electrospinning. The polystyrene molecules were then cross-linked by paraformaldehyde in sulfuric acid to improve the solvent resistance of composite fibers. SEM images conformed the preparation of uniform and smooth composite fibers. FT-IR spectra demonstrated that the polystyrene molecules inside fibers have been sulphonated and crosslinked. Heck reactions were used to evaluate the catalytic performance of these novel composite fibers. The catalysis results show that this composite fiber mat catalyzed Heck reactions could be evidently promoted by using preferred reducing alcohol agent and solvent. Under the optimized reaction conditions, this composite fiber mat could effectively catalyze the Heck reactions of aromatic iodides with n-butyl acrylate to afford the products with satisfied yields. Especially, compared with the particulate Pd/C catalyst, the separation and recycling of this fibrous catalyst from the reaction mixture were significantly improved due to the larger fibrous structure. At last, this fiber catalyst was successfully reused for eight times with little loss of initial catalytic activity, which was even better than the pristine Pd/C catalyst. Hence, embedment of particulate supported metal catalysts inside the crosslinked polystyrene fibers can effectively improve their catalytic performance and handiness.     

Firing properties and corrosion resistance of mullite-Al2TiO5 saggar materials

Conventional refractory materials used for calcining ternary lithium-ion battery cathode materials, such as mullite, cordierite, and magnesia-alumina spinel, are vulnerable to attack by Li(Ni_xCo_yMn_1−x−y)O₂ (LNCM) materials and therefore have a short service life. In order to improve the corrosion resistance of refractory materials to LNCM materials, mullite-Al₂TiO₅ materials with different contents were synthesized in this paper by using calcined mullite powder, TiO₂ powder, and La₂O₃ powder as raw materials, which were calcined at 1500–1600°C temperature, respectively. In this study, the potential of the materials for the preparation of LNCM materials was investigated in terms of its physical properties, resistance to the corrosion of LNCM materials, and resistance to thermal shock. The results showed that mullite-Al₂TiO₅ composites can be successfully synthesized at 1500–1600°C, and the physical properties of the materials met the production requirements. The prepared mullite-Al₂TiO₅ composites also exhibited better physical properties, good corrosion resistance, and proper thermal shock resistance compared with mullite refractories.