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991.
In this work, Bi2XO6 (X = W, Mo) are synthesized at different temperatures. The results of tests find the optimal temperatures of Bi2WO6 and Bi2MoO6 are 180 and 160°C (BW-180, BM-160). Then, BW-180 and BM-160 are further compounded with different contents of CuS. The results of photoelectrochemical (PEC) tests show that CuS can improve the PEC performance of semiconductor materials, and it has better performance when CuS mass fraction is 5%. These maybe the photoelectron potentials generated by CuS/Bi2XO6 (X = Mo, W) heterojunction reduce the combination of photogenerated electrons and holes. When the PEC sensor based on 5%-CuS/BW-180 detects Cr(VI), it has a linear range of 1–80 μmol/L with detection limit of 0.95 μmol/L, while the PEC sensor based on 5%-CuS/BM-160 detects Cr(VI) has a linear range of 0.5–230 μmol/L and a detection limit of 0.12 μmol/L. Thus, 5%-CuS/Bi2XO6 has potential application in hexavalent chromium detection.  相似文献   
992.
综述了高压氢气泄漏后相关燃爆事故及行为研究现状,总结了泄漏自燃、喷射火、气云爆炸等典型燃爆行为的研究现状、方法及结论,探明了典型氢泄漏后燃爆事故的关键控制参数,提出了现有高压氢气泄漏后燃爆风险实验及数值模拟研究存在的不足,并结合实际氢能场景,从实验尺度、初始条件、边界条件等方面对未来的研究方向进行了展望。  相似文献   
993.
以3种化学助剂的化学品安全技术说明书(SDS)信息与气相色谱-质谱联用仪定性分析结果为对比,探讨了油田化学助剂安全技术说明书在完整性、真实性、准确性等方面存在的问题,建议完善SDS审核与监督机制,在识别有害因素时根据SDS、定性定量检测结果、生产工艺及原辅材料分析等内容做出综合判断,使用化学助剂时核实SDS准确性及化学助剂安全性,以采取正确的防控措施。  相似文献   
994.
钢铁企业是CO2排放大户,减少吨钢CO2排放是钢铁企业节约能源、保护环境、走可持续发展道路的必然要求.本研究旨在对钢铁企业产品生命周期清单研究的基础上,识别钢铁企业CO2排放的主要影响因素,提出针对性的减排建议.以某钢铁联合企业的产品生命周期清单模型为平台,同时利用TornadoChart工具,计算得到对企业CO2排放影响较大的因素,然后提出了相应的减排措施.结果表明,转炉流程对于钢铁企业的影响要大于电炉流程;对该企业CO2排放有重大影响和相关影响的因素有:高炉煤气(BFG)的CO2排放系数、连铸坯的钢水单耗、热轧的板坯单耗、转炉的铁水比.减少钢铁联合企业CO2排放的有效措施是采取捕集BFG中的CO2、降低转炉的铁水比、加强副产煤气的回收以及优化企业的产品生产结构.  相似文献   
995.
Journal of Material Cycles and Waste Management - Chinese-made chlorine bypass system has been implemented to achieve stable and trouble-free kiln operation using calcium carbide residue (CCR) with...  相似文献   
996.
To protect the ecosystem of barren mountains, massive Cupressus funebris plantations were allowed in hilly areas of the central Sichuan Basin in the late 1980s. In recent years, Cupressus funebris plantations have faced problems such as biodiversity decline and soil erosion. To study the effects of different forest densities on understory species diversity and soil anti-scourability of Cupressus funebris plantations in Yunding Mountain, a typical sampling method was used to investigate the five different forest densities (1 100, 950, 800, 650, and 500 trees/hm2) and to analyze the correlation between the species diversity index, soil anti-scourability, and root index. In total, 176 species from 128 genera and 69 families were recorded in this area. The number of species in the herb layer was higher than that in the shrub layer. The species diversity index of the shrub layer first increased and then decreased with the decrease in stand density; and the species richness index D and Shannon–Wiener diversity index H showed peak values at a density of 650 trees/hm2. The species richness index D, Shannon–Wiener diversity index H, and Simpson dominance index H’ in the herb layer showed a bimodal trend of increasing, then decreasing, increasing again, and finally decreasing with the decrease in stand density; and the peak values were found at the densities of 650 and 950 trees/hm2. When soil anti-scourability decreased with stand density, it showed a trend of increasing and then decreasing, reaching a peak at a density of 650 trees/hm2. The positive correlation between the species richness index and soil anti-scourability was evident. Thus, 650 trees/hm2 is relatively more conducive to the stability of species diversity and soil anti-scourability in cypress plantations. © 2022 Authors. All rights reserved.  相似文献   
997.
• Antibiotic azithromycin employed in graphite electrode for EAB biosensor. • Azithromycin at 0.5% dosage increased the sensitivity for toxic formaldehyde. • Azithromycin increased the relative abundance of Geobacter. • Azithromycin regulated thickness of electroactive biofilm. Extensive research has been carried out for improved sensitivity of electroactive biofilm-based sensor (EAB-sensor), which is recognized as a useful tool in water quality early-warning. Antibiotic that is employed widely to treat infection has been proved feasible in this study to regulate the EAB and to increase the EAB-biosensor’s sensitivity. A novel composite electrode was prepared using azithromycin (AZM) and graphite powder (GP), namely AZM@GP electrode, and was employed as the anode in EAB-biosensor. Different dosages of AZM, i.e., 2 mg, 4 mg, and 8 mg, referred to as 0.25%, 0.5% and 1% AZM@GP were under examination. Results showed that EAB-biosensor was greatly benefited from appropriate dosage of AZM (0.5% AZM@GP) with reduced start-up time period, comparatively higher voltage output, more readable electrical signal and increased inhibition rate (30%-65% higher than control sensor with GP electrode) when exposing to toxic formaldehyde. This may be attributed to the fact that AZM inhibited the growth of non-EAM without much influence on the physiologic or metabolism activities of EAM under proper dosage. Further investigation of the biofilm morphology and microbial community analysis suggested that the biofilm formation was optimized with reduced thickness and enriched Geobacter with 0.5% AZM@GP dosage. This novel electrode is easily fabricated and equipped, and therefore would be a promising way to facilitate the practical application of EAB-sensors.  相似文献   
998.
Environmental Science and Pollution Research - Although a growing number of original epidemiological studies imply a link between ambient pollution exposure and mortality risk, the findings...  相似文献   
999.
Environmental Science and Pollution Research - In recent years, O3 pollution had been worsening in China and became a major challenge for human health. To evaluate the O3 effects on circulatory and...  相似文献   
1000.
Environmental Science and Pollution Research - This paper examined the nexus between economic growth, energy consumption, urbanization, population growth, and carbon emissions in the BRICS...  相似文献   
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