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[Objective] Facing the global issue of “carbon peak and carbon neutrality”, this study aimed to predict and simulate carbon emissions from energy consumption, explore the feasibility of carbon peaking and carbon neutrality time, and provide theoretical basis for promoting emission reduction. [Methods] In this study, the carbon emission coefficient method was used to calculate the carbon emissions from energy consumption in China from 1986 to 2019. Considering factors from the five aspects of economy, society, environment, energy, and technology, an indicator system including 18 variables was established, and five main factors were screened out by Lasso regression. Based on three machine learning methods and Lasso regression, six carbon emission prediction models including support vector regression (SVR), random forest (RF), back propagation neural network (BP), Lasso-SVR, Lasso-RF, and Lasso-BP were constructed. The models were evaluated based on the mean squared error (MSE) and mean average error (MAE). Combined with the scenario analysis method to set four scenarios of new normalization, green low-carbon, 2 ℃ target, and 1.5 ℃ target, the best prediction model was selected to simulate and analyze China’s energy consumption carbon emissions from 2020 to 2060 under the four scenarios. [Results] Under the four scenarios, with the intensification of emission reduction efforts, China’s carbon peaking platform period is shortened. The time points of carbon peak during the platform period in China are 2035, 2030, 2026, and 2025 respectively, and the peak values are 9.580, 7.448, 6.723 and 6.523 Gt CO2e. Under the 2 ℃ and 1.5 ℃ scenarios, China can achieve carbon neutrality as scheduled. Under all four scenarios China may achieve the 2 ℃ temperature rise target, but under the first two scenarios China will not achieve the 1.5 ℃ target. [Conclusion] Under the four scenarios, the peak value and peak time of China’s energy consumption carbon emissions are different, and the possibility of achieving carbon neutrality is also different. In order to achieve the goals of carbon peak and carbon neutrality as soon as possible, China must promote the optimization of industrial structure and energy system structure, increase investment in green assets, and help the development of emission reduction with technological progress.

Membraneless microfluidic fuel cells (MFCs) have garnered tremendous interest as micropower devices, which exploit the colaminar nature of two aqueous electrolytes to separate the anode and cathode and avoid the membrane usually used in a fuel cell. Our previous research shows that the performance of FeCl3-based MFCs with catalyst-free cathodes is mainly limited by the cathode. To improve the power output of these MFCs, we activated the carbon paper cathode by an electrochemical method in the three solutions (Na2SO4, NaOH, and H2SO4) to improve the electrochemical characteristics of the carbon paper cathode. The surface functionalities and defects, reduction activation of iron ions as the oxidant, cathode resistance, and performance of FeCl3-based MFCs were measured and compared. Our work shows that the electrochemical activation of the carbon paper in different solutions is a simple and effective method to enhance the electrochemical characteristics of the carbon paper cathode and improve the performance of the FeCl3-based MFC. Also, the MFC with the carbon paper cathode activated in the H2SO4 solution reaches the optimum performance: 235.6 mW cm-3 in volumetric power density and 1063.33 mA cm-3 in volumetric limiting current density, which are 1.58 and 1.52 times as much as that of a MFC with an untreated carbon paper cathode, respectively. This best performance can be attributed to the cathode activated in the H2SO4 solution with the largest number of oxygen-containing functional groups, the largest electrochemical active surface area, strongest reduction of iron ions, and least resistance of the cathode.

为高效鉴定食用油脂加工厂污水处理过程的气味组成，采用感官检验以臭阈值量化不同处理工序污水的臭味浓度，并采用气相色谱-离子迁移谱法（GC-IMS）对其挥发性化合物进行分析，并对鉴定出的挥发性化合物进行指纹图谱和主成分分析。结果表明：污水经过处理臭阈值明显降低；GC-IMS鉴定出43种化合物，基本均为含氧有机物，包括酮类、醇类、醛类、酯类、酸类及其他类；总体上各处理工序污水挥发性物质总数和臭阈值的变化规律一致；各处理工序挥发性化合物存在一定差异。综上，GC-IMS是分析食用油脂加工厂污水处理过程气味变化的有效方法。 In order to effectively identify odorants in wastewater treatment process in edible oil plant, the odor concentration of wastewater from different treatment processes was quantified by the threshold odor number(TON) through sensory examination, and the volatile organic compounds (VOCs) were identified using gas chromatography-ion mobility spectrometry (GC-IMS) and analysed by fingerprint plot and principal component analysis. The results showed that the TON of wastewater was significantly reduced after treatment. Forty-three compounds were identified by GC-IMS, all of which were basically oxygen-containing organic compounds including ketones, alcohols, aldehydes, esters, acids and others. The change rule of TON of wastewater was overall consistent with volatile compounds among the treatment processes. There was a variation in VOCs′ overallcomposition among the treatment processes. In conclusion, the GC-IMS technique is an efficient method for analyzing the odor variation of wastewater treatment in edible oil plant.

The objective of this study was to investigate the effect of atractyloside, a promoter of the mitochondrial membrane permeability transition pore (MPTP), on mitochondrial membrane permeability, cristae structure, cytochrome c release and tenderness of postmortem beef and to explore the effect of injury on meat tenderness by releasing cytochrome c and activating caspases. The postmortem longissimus dorsi muscle of adult crossbred cattle was treated or not treated (control) with atractyloside, stored at 4 ℃ and evaluated for mitochondrial ultrastructure, membrane potential, the amount of cytochrome c released to the cytoplasm, cell apoptotic rate, caspase-3 and myofibrillary fragmentation index (MFI) after 0, 12, 24, 72, and 120 h. With postmortem aging time, the number of mitochondrial cristae decreased significantly, and swelling and rupture were observed. The mitochondrial membrane potential decreased significantly, and cytochrome c was released gradually. Starting from 72 h postmortem, the activity of caspase-3 and the apoptosis rate of myocytes increased, and so did MFI. Compared with the control group, atractyloside treatment induced mitochondrial damage by destroying mitochondrial cristae structure, reducing the membrane potential and causing cytochrome c release. In addition, the apoptosis of muscle cells and the fragmentation of myofibrils were accelerated by atractyloside. The opening of the MPTP significantly affected mitochondrial injury in beef after slaughter. Apart from increasing cell membrane permeability, atractyloside also significantly altered the structure of mitochondrial cristae. The internal and external mitochondrial membranes could synergistically regulate the release of cytochrome c, which in turn could affect postmortem tenderization of beef.