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1.
Two types of spherical zirconyl oxalate aqueous sols were successfully customized by a reverse micelles-mediated aqueous sol-gel process, and the sols were sequentially spin-coated on porous supports to prepare ZrO2 loose/tight bilayer ultrafiltration membranes. After three times of spin-coating process, a defect-free ZrO2 loose ultrafiltration membrane with pure water permeability of 110.5 ± 2.25 L m?2 h-1 bar-1, molecular weight cut-off (MWCO) of 16.5 kDa and excellent rejection of up to 97.5 % for bovine serum albumin was fabricated. Then, the loose ultrafiltration membrane was used as a substrate to prepare ZrO2 tight ultrafiltration membrane. Performances of tight ultrafiltration membrane regarding to permeability, retention of polyethylene glycol and treatment of dyes wastewater were evaluated. The tight ultrafiltration membrane with a thickness of 200 nm exhibited a pure water permeability of 22.5 ± 0.3 L m-2 h-1 bar-1 and MWCO of 1150 Da. Additionally, the rejections of methyl red and methyl orange by the tight ultrafiltration membrane were both <65 %, while of alizarin red, direct red, bromocresol green and methyl blue achieved maximum values of 98.5 %, 99.2 %, 99.5 % and 99.6 %, respectively. The fouled membranes could restore the virgin performance for reuse by cleaning and low-temperature calcination.  相似文献   
2.
丁华 《硫酸工业》2021,(1):6-10
无干燥塔就无串酸,只产w(H2SO4)98%产品酸,开停车时干气来自吸收塔。比较了无干燥塔的带酸热回收硫磺制酸装置在亚热带湿润气候下的4种工况,副产蒸汽量与空气中水分相关,气温越高、湿度越大,蒸汽产量越多,且中压蒸汽产率更高。采用空冷增湿酸冷却器,可实现无循环水,将干吸余热全部回收,蒸汽产率可达2 t/t。若用部分冷凝省煤器,还可再提高蒸汽有效能,使部分低压蒸汽转变成中压蒸汽。该装置可直接掺烧废酸、酸性废水及含硫废气,成为含硫废弃物协同处理装置,不仅增加能量回收率,且低成本地处置含硫废物。  相似文献   
3.
The damage induced in 3C-SiC epilayers on a silicon wafer by 2.3-MeV Si ion irradiation for fluences of 1014, 1015, and 1016 cm−2, was studied by conventional and high-resolution transmission electron microscopy (TEM/HRTEM). The evolution of extended defects and lattice disorder is followed in both the 3C-SiC film and Si substrate as a function of ion fluence, with reference to previous FTIR spectroscopy data. The likelihood of athermal unfaulting of native stacking faults by point defect migration to the native stacking faults is discussed in relation to damage recovery. Threshold energy densities and irradiation doses for dislocation loop formation and amorphous phase transformation are deduced from the damage depth profile by nuclear collisions. The role of electronic excitations on the damage recovery at high fluence is also addressed for both SiC and Si.  相似文献   
4.
Fast, simple, accurate, and inexpensive methods for obtaining analyte concentration data are desirable in the industrial sector. In the present study, the use of Fourier transform mid‐infrared (FT‐MIR) spectroscopy, combined with partial least squares (PLS) regression, was investigated as a tool for real‐time monitoring of processes of ethanol absorption in glycols. Calibration was performed using simple synthetic samples containing ethanol, water, and monoethylene glycol (MEG) or diethylene glycol (DEG). The PLS models presented excellent performance, with correlation coefficients (R2) close to unity and root‐mean‐square errors of cross‐validation (RMSECV) and prediction (RMSEP) lower than 2% of the calibration data ranges for both analytes (ethanol and water) in both absorbents (MEG and DEG). The monitoring technique developed has potential to be applied in absorption processes and could also be used in other large‐scale unit operations, providing information in real time and enhancing process control.  相似文献   
5.
In recent years, artificial intelligence (AI) is being increasingly utilised in disaster management activities. The public is engaged with AI in various ways in these activities. For instance, crowdsourcing applications developed for disaster management to handle the tasks of collecting data through social media platforms, and increasing disaster awareness through serious gaming applications. Nonetheless, there are limited empirical investigations and understanding on public perceptions concerning AI for disaster management. Bridging this knowledge gap is the justification for this paper. The methodological approach adopted involved: Initially, collecting data through an online survey from residents (n = 605) of three major Australian cities; Then, analysis of the data using statistical modelling. The analysis results revealed that: (a) Younger generations have a greater appreciation of opportunities created by AI-driven applications for disaster management; (b) People with tertiary education have a greater understanding of the benefits of AI in managing the pre- and post-disaster phases, and; (c) Public sector administrative and safety workers, who play a vital role in managing disasters, place a greater value on the contributions by AI in disaster management. The study advocates relevant authorities to consider public perceptions in their efforts in integrating AI in disaster management.  相似文献   
6.
喷雾焙烧法是针对不锈钢混酸废液的全酸回收工艺方法,不仅可以实现废酸中游离酸的回收,还可以实现化合酸及金属元素的回收。针对青拓集团福建鼎信科技有限公司不锈钢混酸废液再生中试项目,介绍了喷雾焙烧法不锈钢混酸再生机组的技术方案、运行指标,并与引进机组进行了主要技术经济指标对比分析,各项指标均达到或超过了国外同类机组水平。同时,对该技术的进一步研究方向进行了展望。  相似文献   
7.
Greenhouse gases emitted into the atmosphere by burning of fossil fuels cause global warming. One option is obtaining biodiesel. Nannochloropsis oculata was cultured under different light intensities and reactors at 25°C for 21 days with f/2 medium to assess their effects on cell density, lipid, and fatty acids (FAs). N. oculata improved cell density on fed-batch glass tubular reactor (7 L) at 200 μmol E m−2 s−1, yielding 3.5 × 108 cells ml−1, followed by fed-batch Erlenmeyer flask (1 L) at 650 μmol E m−2 s−1 with 1.7 × 108 cells ml−1. The highest total lipid contents (% g lipid × g dry biomass−1) were 44.4 ± 0.8% for the reactor (1 L) at 650 μmol E m−2 s−1 and 35.2 ± 0.2% for the tubular reactor (7 L) at 200 μmol E m−2 s−1, until twice as high compared with the control culture (Erlenmeyer flask 1 L, 80 μmol E m−2 s−1) with 21.2 ± 1%. Comparing the total lipid content at 200 μmol E m−2 s−1, tubular reactor (7 L) and reactor 1 L achieved 35.2 ± 0.2% and 28.3 ± 1%, respectively, indicating the effect of shape reactor. The FAs were affected by high light intensity, decreasing SFAs to 2.5%, and increased monounsaturated fatty acids + polyunsaturated fatty acids to 2.5%. PUFAs (20:5n-3) and (20:4n-3) were affected by reactor shape, decreasing by half in the tubular reactor. In the best culture, fed-batch tubular reactor (7 L) at 200 μmol E m−2 s−1 contains major FAs (16:0; 38.06 ± 0.16%), (16:1n-7; 30.74 ± 0.58%), and (18:1n-9; 17.15 ± 0.91%).  相似文献   
8.
Interfacial properties are of critical importance to various separation applications. In heavy oil recovery, for example, a low oil–water interfacial tension (IFT) benefits the separation of heavy oil from their host rocks, which becomes problematic in the later stage of oil–water separation. CO2-responsive surfactants were investigated to enhance the overall heavy oil recovery by switching their interfacial activity to the desired state in each stage. The surfactants at interfacially active state greatly enhanced the separation of heavy oil from hosting solids, as demonstrated by measuring contact angle and oil liberation using a custom-designed on-line visualization system. Meanwhile, the resulting heavy oil-in-water emulsions could also be easily demulsified by the bubbling of CO2 gas, which switched off the interfacial activity of the surfactants. Furthermore, CO2-responsive surfactants could be partially recycled in process water to improve sustainability, making CO2-responsive surfactants to be promising chemical aids in heavy oil production and many other vital industries.  相似文献   
9.
同轴套管式深井换热器是一种开采地热能的有效方式,为了提高其换热器的换热性能,采用有限体积分析方法,开展了同轴套管式深井换热器传热性能研究。通过建立近地热源区域的同轴套管式深井换热器三维传热模型,分析了入口流速、入口温度以及保温管距井底距离等关键因素对换热器采热功率的影响,结果表明:入口流速由0.1 m/s增加到1 m/s,采出温度降低了9.82 K,采热功率增加了7倍;入口温度从288 K增加到308 K,采出温度增加了13.61 K,采热功率下降了17.2%;距井底900 mm距离降低到 100 mm,采出温度增加1.91 K,采热功率增加了6.57%。  相似文献   
10.
铱由于其物理、化学性质稳定,被广泛应用于航空、电子、催化等高新技术行业,铱二次资源回收意义重大。基于对40多篇文献的分析,介绍了含铱废料的来源,综述了从不同废料中回收提纯铱的工艺,从铱金属和合金废料中回收铱包括溶解和精炼等工序,溶解的方法主要有碎化活化溶解,碱熔融预处理等;精炼的工艺主要有沉淀法、离子交换法、萃取法、氢还原法、高温氧化挥发法等。根据原料成分以及对铱纯度的要求,各种除杂的方法可以联合使用。  相似文献   
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