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1.
魏宁  刘胜男  魏凤  李小春 《环境科学》2023,44(12):6621-6629
中国水泥行业面临巨大的碳达峰与碳中和压力.CO2捕集利用与封存(CCUS)技术是能够实现化石资源低碳利用的碳减排技术.在中国水泥企业数据基础上,采用全流程CCUS系统模型(ITEAM-CCUS)评估CCUS的碳减排潜力对水泥企业碳中和非常重要.模型从源汇匹配距离、捕集率、CCUS技术和技术水平这4个方面设置了10种情景,完成了水泥行业的企业筛选、场地筛选、CCUS技术经济评估和源汇匹配,初步回答了水泥企业结合CCUS的封存场地、减排规模、成本范围和优先项目分布等关键问题.在250 km匹配距离、85%净捕集率、CO2-EWR技术和当前技术水平情景,44%的水泥企业可以利用CO2强化地下水开采(CO2-EWR)技术开展碳减排,累计年碳减排量为6.25亿t,平准化成本为290~1838元·t-1;具有全流程CO2-EWR早期示范优势的地区为新疆、内蒙古、宁夏、河南和河北等.水泥企业开展全流程CCUS项目技术可行,可以实现大规模CO2减排,低成本项目具有早期示范机会.研究结果可为水泥行业低碳发展和CCUS商业化部署提供定量参考.  相似文献   
2.
赖金林  齐实  崔冉冉  廖瑞恩  唐颖  李鹏 《环境科学》2023,44(12):6833-6846
西南高山峡谷区是我国典型生态脆弱区,认识其植被变化特征及影响因素可以为西南高山峡谷区生态环境建设对策的制定提供理论依据,对实现区域经济、环境以及生态和谐统一发展,具有一定的现实意义.基于2000~2019年NDVI、社会经济因子和自然因子数据集,采用一元线性回归法、Hurst指数、地理探测器模型和变异系数等方法分析了西南高山峡谷区NDVI时空变化及稳定性特征,并探讨了NDVI空间分异影响因素.结果表明:①空间上看,植被呈现东南高,西北低的分布格局,中高和高植被覆盖的区域面积占比71.71%,植被覆盖总体处于较高水平.时间上看,植被呈现改善趋势的区域面积占比85.90%,恢复效果明显,且未来植被变化趋势还将以改善为主.②高程、植被类型和土壤类型是影响NDVI空间分异的主导因子,q值均不低于0.40;气温和降雨量为次要因子,q值分别为0.274和0.225.双因子交互作用增强了单因子的影响力,表现为双因子增强和非线性增强两种关系,其中高程∩植被类型组合q值最高为0.714,其次是高程∩土壤类型组合q值为0.688.③研究时段内NDVI整体稳定性较好,低波动变化和较低波动变化的区域面积占比为89.95%;而中等以上波动的区域面积占比为10.05%,集中在海拔高、气温低、降雨少、土壤贫瘠和植被较差等生态环境相对脆弱的区域.植被变化是多因素综合作用的结果,需因地制宜,有针对性地采取不同策略修复西南高山峡谷区生态环境.  相似文献   
3.
采用高效液相色谱-二极管阵列检测器对6种PAEs类物质进行测定,并对梯度洗脱条件、流速、检测波长等影响化合物色谱响应的关键参数进行优化。综合考虑样品测试效率、分析精度、实际样品中存在杂质干扰等因素,确定以乙腈-水为流动相进行梯度洗脱,洗脱0~11 min流动相乙腈-水梯度比例为50∶50,11 min后流动相调整为100%乙腈,各化合物均能完全分离;色谱分析流速为0.8 m L/min;PAEs的最佳吸收波长为225 nm。在优化的色谱条件下,6种PAEs的线性良好,相关系数均大于0.999 8,仪器检出限为0.08~0.12 mg/L,保留时间、峰面积的相对标准偏差分别为0.02%~0.60%、0.13%~0.86%。方法灵敏度较高,适合土壤等邻苯二甲酸酯含量较高基质样品的快速分析。  相似文献   
4.
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques.  相似文献   
5.
顾广悦  李磊  相坤  端木祥玲  刘海静 《安全》2020,(2):27-35,10
为了能够有效提升综合管廊内火灾自动报警系统的准确性和可靠性,本文采用火灾实体试验的方法,通过对各类型火灾自动报警探测器响应时间的情况进行分析和比较,研究综合管廊电力舱内常用探测器的性能。研究结果表明:接触式缆式线型感温火灾探测器可以较早的探测到电缆温度异常变化的现象,可用于早期预警。点型感烟探测器对烟粒子浓度较为敏感,可用于综合管廊电力舱室的空间探测。分布式光纤型感温火灾探测器对明火温度的变化较为敏感,作为空间型的火灾探测器比较可靠。  相似文献   
6.
The gas detector layout should be highly attuned to combustible gas leakage and attain a good reliability in avoiding detector malfunction, which is an important guarantee for the normal production of the chemical industry and other related enterprises. Herein, a gas detector layout optimization method based on double coverage and reliability is proposed. The key gas leakage monitoring area is determined through layout scene field investigation. To improve the detection probability and detection system reliability, the dual coverage target and voting mechanism are set, and the gas detector layout is determined with the ray-casting algorithm according to the coverage target. Combined with FLACS software to simulate a variety of typical leakage conditions under different layout scenarios, the relationship between the leaked gas concentration detected by gas detectors in each layout scheme and time is obtained, and the gas leakage detection probability in each layout scheme, number of detectors that can trigger the alarm, shortest time to trigger the alarm and reliability are comprehensively evaluated. The decision-maker selects the final gas detector layout plan according to the evaluation results and actual site needs. The study shows that the detection probability of each layout scheme set according to the double coverage is high, and multiple detectors can trigger the alarm (up to 100%), which ensures that the alarm can be triggered within 10 s under all applicable conditions. According to the evaluation results, the decision-maker can obtain a layout scheme that not only agrees with the actual site conditions but also attains a high detection probability, short detection time and strong reliability.  相似文献   
7.
• Fe(III) accepted the most electrons from organics, followed by NO3, SO42‒, and O2. • The electrons accepted by SO42‒ could be stored in the solid AVS, FeS2-S, and S0. • The autotrophic denitrification driven by solid S had two-phase characteristics. • A conceptual model involving electron acceptance, storage, and donation was built. • S cycle transferred electrons between organics and NO3 with an efficiency of 15%. A constructed wetland microcosm was employed to investigate the sulfur cycle-mediated electron transfer between carbon and nitrate. Sulfate accepted electrons from organics at the average rate of 0.84 mol/(m3·d) through sulfate reduction, which accounted for 20.0% of the electron input rate. The remainder of the electrons derived from organics were accepted by dissolved oxygen (2.6%), nitrate (26.8%), and iron(III) (39.9%). The sulfide produced from sulfate reduction was transformed into acid-volatile sulfide, pyrite, and elemental sulfur, which were deposited in the substratum, storing electrons in the microcosm at the average rate of 0.52 mol/(m3·d). In the presence of nitrate, the acid-volatile and elemental sulfur were oxidized to sulfate, donating electrons at the average rate of 0.14 mol/(m3·d) and driving autotrophic denitrification at the average rate of 0.30 g N/(m3·d). The overall electron transfer efficiency of the sulfur cycle for autotrophic denitrification was 15.3%. A mass balance assessment indicated that approximately 50% of the input sulfur was discharged from the microcosm, and the remainder was removed through deposition (49%) and plant uptake (1%). Dominant sulfate-reducing (i.e., Desulfovirga, Desulforhopalus, Desulfatitalea, and Desulfatirhabdium) and sulfur-oxidizing bacteria (i.e., Thiohalobacter, Thiobacillus, Sulfuritalea, and Sulfurisoma), which jointly fulfilled a sustainable sulfur cycle, were identified. These results improved understanding of electron transfers among carbon, nitrogen, and sulfur cycles in constructed wetlands, and are of engineering significance.  相似文献   
8.
Information on population sizes and trends of threatened species is essential for their conservation, but obtaining reliable estimates can be challenging. We devised a method to improve the precision of estimates of population size obtained from capture–recapture studies for species with low capture and recapture probabilities and short seasonal activity, illustrated with population data of an elusive grasshopper (Prionotropis rhodanica). We used data from 5 capture–recapture studies to identify methodological and environmental factors affecting capture and recapture probabilities and estimates of population size. In a simulation, we used the population size and capture and recapture probability estimates obtained from the field studies to identify the minimum number of sampling occasions needed to obtain unbiased and robust estimates of population size. Based on these results we optimized the capture–recapture design, implemented it in 2 additional studies, and compared their precision with those of the nonoptimized studies. Additionally, we simulated scenarios based on thresholds of population size in criteria C and D of the International Union for Conservation of Nature (IUCN) Red List to investigate whether estimates of population size for elusive species can reliably inform red-list assessments. Identifying parameters that affect capture and recapture probabilities (for the grasshopper time since emergence of first adults) and optimizing field protocols based on this information reduced study effort (−6% to −27% sampling occasions) and provided more precise estimates of population size (reduced coefficient of variation) compared with nonoptimized studies. Estimates of population size from the scenarios based on the IUCN thresholds were mostly unbiased and robust (only the combination of very small populations and little study effort produced unreliable estimates), suggesting capture–recapture can be considered reliable for informing red-list assessments. Although capture–recapture remains difficult and costly for elusive species, our optimization procedure can help determine efficient protocols to increase data quality and minimize monitoring effort.  相似文献   
9.
制备了钾改性正硅酸锂(K-Li4SiO4),并对其进行了自活化,考察了活化后K-Li4SiO4吸附剂在不同温度和CO2浓度气氛中吸附CO2的性能及动力学行为。总体而言,吸附剂的CO2吸附能力随着温度的升高、CO2浓度的增加而提升。在700℃、100%体积分数CO2气氛中吸附剂的吸附量最大,可达7.9 mmol/g,吸附剂的利用率为95.2%。利用双指数模型能够很好地描述吸附剂在各个温度以及各个CO2浓度气氛下的CO2吸附过程。吸附活化能随着CO2气氛浓度的升高而降低,CO2体积分数为20%,50%,100%时的吸附活化能分别为26448,14035,6178 J/mol。  相似文献   
10.
Carbamate compounds are an important group of cholinesterase inhibitors. There is a need for creating awareness regarding the risks of the inadequate carbamate use in the residential areas due to potential adverse human effects. Carbaryl is a commonly used pesticide worldwide. A simple, fast, and high-throughput method was developed employing liquid chromatography with fluorescence detector to determine carbaryl residues in rat feces. The extraction was performed by using a rapid, easy, cheap, effective, reliable, and safe (QuEChERS) method, using acetonitrile as the extracting solvent. The parameters for the performance of the extraction method were optimized, such as ratio of mass of sample per volume of extraction solvent, QuEChERS content, and cleanup columns. Linear response was obtained for all calibration curves (solvent and matrix-matched) over the established concentration range (5–500 μg/L) with a correlation coefficients higher than 0.999. The achieved recovery was 97.9% with relative standard deviation values of 1.1% (n = 4) at 167 μg/kg fortified concentration level and the limits of detection and quantification were 27.7 and 92.3 µg/kg, respectively.  相似文献   
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