寒冷地区某既有办公建筑围护结构优化改造研究

既有公共建筑能耗中,围护结构节能潜力巨大。以兰州某既有办公建筑为例,采用DeST-C软件模拟围护结构不同材料厚度、窗型,得出系列负荷,通过对数据分析、比较,得出如下结论:外墙外保温适宜材料为50mm的挤塑板,最大热负荷节能率为45.66%;屋面适宜保温材料为65mm的挤塑板,最大热负荷节能率为4.25%;外窗各个朝向全部更换玻璃,推荐选用内张膜中空玻璃(双膜),最大热负荷节能率为7.36%;单独更换南向外窗材料,推荐选用真空镀膜复合中空玻璃,最大热负荷节能率为1.78%。     

Novel Bi-Doped Amorphous SnOx Nanoshells for Efficient Electrochemical CO2 Reduction into Formate at Low Overpotentials

Engineering novel Sn-based bimetallic materials could provide intriguing catalytic properties to boost the electrochemical CO₂ reduction. Herein, the first synthesis of homogeneous Sn_1−xBi_x alloy nanoparticles (x up to 0.20) with native Bi-doped amorphous SnO_x shells for efficient CO₂ reduction is reported. The Bi-SnO_x nanoshells boost the production of formate with high Faradaic efficiencies (>90%) over a wide potential window (−0.67 to −0.92 V vs RHE) with low overpotentials, outperforming current tin oxide catalysts. The state-of-the-art Bi-SnO_x nanoshells derived from Sn_0.80Bi_0.20 alloy nanoparticles exhibit a great partial current density of 74.6 mA cm⁻² and high Faradaic efficiency of 95.8%. The detailed electrocatalytic analyses and corresponding density functional theory calculations simultaneously reveal that the incorporation of Bi atoms into Sn species facilitates formate production by suppressing the formation of H₂ and CO.     

固废制备微晶泡沫玻璃的研究进展

为实现固体废弃物的高值化利用，从微晶泡沫玻璃的制备机理、工艺流程及温度制度等方面分析了工业固体废弃物制备微晶泡沫玻璃的可行性，重点论述了金属矿尾矿、赤泥、高炉矿渣、煤矸石、粉煤灰等固体废弃物制备微晶泡沫玻璃的国内外研究进展，并对微晶泡沫玻璃的研究和发展趋势进行了展望。     

千年古陂为何久盛不衰

泰和县槎滩陂修建于公元937年,在牛吼江上游一个急拐弯处用土木作坝截流,顺应弯道河势开挖一弧形引水河段,利用弯道水流运动特性,灌渠引水口正面引水、陂坝侧面溢流,保障了工程防洪安全、运行可靠.为了保障陂坝下游河道农业用水和河道生态用水,在槎滩陂下游3.5km修建碉石陂,买山置田准备了陂坝维修管理的材料和经费.逐步建立了一乡绅大户为陂长、受益农户广泛参与的管理制度.一千多年来盛久不衰、活力无穷,经过不断维修改造,现在灌溉农田3000hm2以上.槎滩陂是我国古代农业灌溉文明的代表性工程,是人水和谐相处的杰出典范,成为世界灌溉工程遗产.     

Advances in the in vitro digestion and fermentation of polysaccharides

In vitro digestion models are widely used to study the structural changes, digestion and release of food components under simulated gastrointestinal conditions. As compared to the in vivo digestion tests, the in vitro digestion reflects the digestion and utilisation of food after ingestion and has the advantages of being time consuming, inexpensive, reproducible and free from moral and ethical restrictions. This study reviewed the current research studies on the in vitro simulated digestion of polysaccharides conducted in the last 5 years and focused on the oral, gastric and intestinal digestion models, with the aim of providing a basis for the further testing of changes in the content, structure and active ingredients of polysaccharides before and after digestion.     

Revisiting the Parallel Strategy for DOACROSS Loops

Journal of Computer Science and Technology - DOACROSS loops are significant parts in many important scientific and engineering applications, which are generally exploited pipeline/wave-front...     

瞬变电磁法不同工作装置在强干扰区的综合应用

目前瞬变电磁法勘探广泛运用在煤矿系统,主要解决地下水的问题.随着科技的发展和进步,瞬变电磁法勘探仪器大致分2类,国外仪器一般采用大功率、大线框的大定源框内回装置;国内仪器一般采用小功率小线圈、低电压、高电流的重叠回线装置.在作业过程中,瞬变电磁法发射线框与接收设备受电磁干扰较为严重,不同的工作装置优势不同,抗干扰能力不同.通过对山西潞安集团李村矿的工作研究,证明了采用不同工作装置在高压线附近进行勘探,可起到互补的作用,达到勘探的目的 .     

Lead-free sodium niobate nanowires with strong piezo-catalysis for dye wastewater degradation

In this work, the hydrothermally-synthesized sodium niobate nanowires were used to decompose Rhodamine B dye solution through the piezo-catalytic effect. With the sodium niobate catalyst, a high piezo-catalytic degradation ratio of ～80% was achieved under the excitation of vibration for the Rhodamine B dye solution (～5?mg/l). These active species in the catalytic process, hydroxyl radicals and superoxide radicals with the strong oxidation ability, were also observed, which confirmed the key role of piezoelectric effect for piezo-catalysis. The piezo-catalysis of sodium niobate nanowires provides a high-efficiency and reusable tool in application in depredating the dye wastewater.     

Fabrication of novel silicon carbide-based nanomaterials with unique hydrophobicity and microwave absorption property

Novel SiC-based nanomaterials, namely the nitrogen and aluminum co-doped SiC@SiO₂ core-shell nanowires and nitrogen-doped SiO₂/Al₂O₃ nanoparticles, have been fabricated through a facile thermal treatment process based on the chemical vapor deposition and vapor-liquid reaction. These nanomaterials show remarkable hydrophobicity with a water contact angle (CA) over 140°, which are aroused by the surface zigzag morphology of the nanostructures and the hydrocarbyl groups generated during the preparation process. Moreover the nanocomposites also exhibit relatively prominent microwave absorption (MA) properties in the frequency range of 2.0-18.0 GHz. The minimum reflection loss (RL) value as low as −23.68 dB can be observed at 14.16 GHz when the absorber thickness is 2.6 mm with a loading rate of 16.7 wt%. And the nanocomposites-based absorbent can achieve an effective absorption bandwidth (RL < −10 dB) of 4.48 GHz with the absorbent thickness of 2.5 mm. This enhanced microwave attenuation performance can be attributed to multiple polarizations and perfect impedance matching conditions, as well as multiple internal reflections. These marvelous properties make these N and Al co-doped SiC@SiO₂ core-shell nanowires and N-doped SiO₂/Al₂O₃ nanoparticles display extensive application potential as MA materials in harsh environment.