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This essay explores the concept of activity-based carbon neutrality as a critical component in achieving carbon emission reduction targets. With the Chinese government’s commitment to carbon sequestration by 2030 and carbon neutrality by 2060. activity-based carbon neutrality has gamed prominence as a hot topic in environmental discussions. The essay emphasizes the significance of activity-based carbon neutrality in promoting public awareness and participation in carbon reduction efforts. It highlights the existing research gap in this field and stresses the need for exploring methodologies to achieve activity-based carbon neutrality. The essay outlines the accounting standards for activity-based carbon neutrality, focusing on large-scale events and offering practical examples of carbon emission reduction measures during the preparation, execution, and conclusion phases of activities. Additionally, it introduces carbon offsetting methods such as carbon quotas and carbon credits. The article also presents a specific case study of the “Six-Five Environment Day National Event” held in Liaoning Province, which successfully achieved carbon neutrality through various initiatives. Overall, the essay encourages further investigation into activity-based carbon neutrality to enhance overall carbon reduction efforts.

The combustion characteristics of ammonia/hydrogen premixed laminar flow and the effect of hydrogen on the combustion performance of ammonia fuel were studied. First, the corresponding model of ammonia/ hydrogen premixed laminar combustion is established by using GRI3.0 mechanism, Konnov mechanism, Mei mechanism, Okafor mechanism, and Otomo mechanism respectively. Second, the simulation results are compared with the experimental results. It is found that the Mei mechanism and Okafor mechanism are more suitable for ammonia/ hydrogen premixed laminar combustion. On this basis, the effects of equivalent ratio, hydrogen ratio, and initial temperature on laminar flame velocity, maximum combustion temperature, and NO mole fraction were studied. The results show that the laminar flame velocity, the maximum combustion temperature, and the mole fraction of NO first increase and then decrease with the increase of the equivalent ratio, and the laminar flame velocity reaches the maximum when the equivalent ratio is 1.1. At the same time, with the increase of hydrogen ratio and initial temperature, the maximum combustion temperature increases first and then decreases. The mole fraction of NO increased with the increase of hydrogen ratio and initial temperature. The results show that mixing hydrogen in ammonia can improve the combustion characteristics of ammonia.

To explore the strength change law and solidification mechanism of cement solidified heavy metal lead and chromium contaminated soil, ordinary Portland cement (OPC) and magnesium phosphate cement (MPC) were used for solidification/stabilization treatment. Through the unconfined compressive strength (UCS) test, scanning electron microscopy (SEM) and the leaching toxicity test, the microscopic characteristics of the cement type, the cement content, the ion type, the ion concentration, and the age and their influence law on the strength characteristics of heavy metal contaminated soil were obtained. The UCS test shows that the compressive strength increases with the cement content and age. When OPC and MPC were used to solidify lead and chromium heavy metal contaminated soil, the compressive strength of OPC was greater than that of MPC, and when the curing age was 28 days, 20% of OPC and MPC satisfied the landfill requirements. The leaching toxicity test showed that after the solidification/stabilization of heavy metal lead and chromium contaminated soil by OPC and MPC, the leaching content of lead ions in the leaching solution conforms to the national limit. For chromium contaminated soil, the concentration was less than or equal to 5000mg/kg, which conform to the limit standard. When the concentration was 10000mg/kg, the content exceeded the limit. Therefore, heavy metal lead contaminated soil is more easily stabilized than chromium contaminated soil. Microscopic tests show that OPC solidified heavy metal contaminated soil is solidified/stabilized by heavy metal ions through hydration products, namely, ettringite and amorphous cementing materials. MPC is obtained by the hydration reaction of magnesium oxide and ammonium dihydrogen phosphate to form struvite, and heavy metal ions are encapsulated in the lattice to achieve solidification/stabilization.

The small hydropower stations have reached a new balance after years of operation. The ecological balance of the river would been broken by the dam removal and the reservoir area above the dam would disappear. Consequently, a series of changes occurred in water depth, velocity of flow, the concentration of organic and inorganic nutrients, distribution and form of organic matter, aquatic organism, etc. It is unclear what would happen for the hydrodynamic conditions, sediment characteristics and aquatic organism community structure of the reservoir area and the lower reaches after the dam removal. Therefore, it is urgent to study the impact of dam removal on the transportation and redistribution of organic debris and the potential ecological effects with benthos as indicators in the river where the small hydropower station is located.

In the new era of China’s development for higher vocational college students have new quality development requirements, especially in terms of ideological quality, college students in the new era are required to have patriotic feelings and practical action, correct overall view of world development, and conscious view of global ecological environment protection. At a higher vocational college in Anhui province for two months investigation and study of the topic, through the data analysis found that some problems existing in the college students in the new era of ideological quality development: some college students of level of concern for domestic event and domestic security is not high, and the patriotic practical actions need to be further improved; Some of them have a shallow understanding of the international situation, and the ideological quality of a few college students does not meet the requirements of The times; College students have nearly for ecological environment protection is the lack of action. It puts forward the corresponding countermeasures and Suggestions: Guiding the college students pay attention to the national development, and to the right side of thinking, actively safeguard national interests; Guiding the youth to learn to distinguish right from wrong, and form a correct global vision and the soul of thought; Through the education of higher vocational college students to learn ecological security concept of national overall security, enhance their awareness of environmental protection, ecological security and the ability to consciously maintain ecological security.

In order to meet the requirements of partial discharge (PD) detection of electrical equipment in substation station area, the ultra-high frequency (UHF) antenna with broadband, high gain and horizontal plane (H-plane) omnidirectional is studied and designed as a PD sensor. By analyzing the characteristic impedance and structural characteristics of the biconic antenna, it is determined to be an UHF omnidirectional wideband antenna for detecting PD. The influence of structural parameters such as half-cone angle and vertebral body height on the antenna performance is simulated. At last, a double cone antenna is made and its bandwidth, directional pattern, gain and equivalent height are tested.

China has established and implemented marine ecological conservation red line (MECRL) system to strengthen the bottom line constraints and ensure ecological security. This paper introduces the concept of MECRL and the process of overall consideration of the national MECRL delineation, which is defined “spatial-division + differential control measures”. The MECRL in Bohai Sea pilot and delineation of MECRL nationwide are introduced. At present, MECRL accounts for about 30 percent of the total coastal management area, providing a good institutional guarantee for protecting marine ecology and guiding the good formation of a scientific marine spatial layout in china.

This is a research on the change of nutrients and its structure in the Pearl River Estuary by the principal component analysis (PCA) according to the data and materials on water quality observation in the last 30 years around the Pearl River Estuary. Results showed that inorganic nitrogen (DIN) presented an obvious increase trend in the last 30 years, while phosphate and silicate presented an outstanding decrease trend in this area by the influence of human activities. The average N/P ratio increased by 1.44 times, the Si/N ratio decreased by 66.8%, the Si/P ratio decreased by 18.5%, and the structure of nutrients changed significantly. According to the results of PCA, the first two principal components (PC) were extracted. PC1 was associated with GDP, population, industrial output value and wastewater discharge, which explained 80.9% of the variance. PC2 was characterized by cultivated land area, which explained 14.6% of the variance. It indicates that the change of nutrients content and structure in the Pearl River Estuary was closely related to economic development and industrial pollution discharge, and the effect of the change of land use and land cover on the change of nutrients should not be ignored.

Desmodium styracifolium is one of the traditional Chinese herbs. In the present study, membrane-based technologies were used to separate and concentrate of the total flavone glycosides fraction from D. styracifolium. The extracts flowed through an ultrafiltration membrane which MWCO (molecular weight cut-off) is 30KDa and the permeate was concentrated by MWCO-1KDa nano-filtration membrane. The solid content of the membrane concentrated extracts of D. styracifolium (MEDs) was 26.5 mg/ml. Moreover, the content of vicenin-2, schaftoside and isovitexin in MEDs were 4.88 %, 9.76 %, 1.89 % respectively. The assay in vitro showed MEDs has better anti-inflammatory effect which partly proved that our membrane-based processes for separation and concentration of flavone glycosides from D. styracifolium is reliable and practicable.

Flying-ash erosion is the prime reason of the tube failure, involving the economy and safety of coal-fired power plants. To address this issue, computational fluid dynamics (CFD) is applied to this paper, which is coupled with the erosion profile calculation based on the dynamic mesh. The tube profile is analyzed under the flying-ash erosion, and the heat transfer process is further taken into account. The results indicate that as time goes on, the impact frequency and the incident angle decrease at the lower angle and increase at the higher angle. With time going on, the peak value becomes smaller at the saddle-shaped erosion rate curve, and the position of the peak value moves towards the higher angle. Meanwhile, both sides of the saddle-shaped curve expand towards the higher angle. That is, the erosion rate and the erosion loss become higher. The Nusselt number grows slightly and the trend grows faster as time goes on. The erosion profile leads to raising the temperature gradient at the angle of 0°, which induces the tube to rupture ultimately.

This paper discusses the distribution regularity of ship arrival and departure and the method of prediction of ship traffic flow. Depict the frequency histograms of ships arriving to port every day and fit the curve of the frequency histograms with a variety of distribution density function by using the mathematical statistic methods based on the samples of ship-to-port statistics of Fangcheng port nearly a year. By the chi-square testing: the fitting with Negative Binomial distribution and t-Location Scale distribution are superior to normal distribution and Logistic distribution in the branch channel; the fitting with Logistic distribution is superior to normal distribution, Negative Binomial distribution and t-Location Scale distribution in main channel. Build the BP neural network and Markov model based on BP neural network model to forecast ship traffic flow of Fangcheng port. The new prediction model is superior to BP neural network model by comparing the relative residuals of predictive value, which means the new model can improve the prediction accuracy.

In this paper, the current bicycle wheel was replaced by the ones which composed by the wheel hub with Glassfiber Reinforced Plastic (alkali free thin-walled cylinder material, hereinafter referred to as GFRP) material and the protective components made up of rubber outer pneumatic pad. With the help of the basic theory of elastic-plastic mechanics, the finite element “Nonlinear buckling” analysis of the wheel was carried out. The results show that the maximum elastic deformation of the wheel hub and the critical value of buckling failure load were restricted by the elasticity under the condition of external loads. Considering with the tensile strength and elastic modulus of the GFRP value of the material, it is demonstrated that the material is feasible to be used for wheel hub.

In this paper, MAN 6S35ME-B9 two-stroke diesel engine is taken as the research object. By constructing a detailed combustion reaction mechanism including CH4, C4H10O, nitrides and other substances, CHEMKIN-PRO is used to simulate the same fuel mixing ratio and excess air coefficient. Under the condition of 1.5, the temperature, NO mole fraction and NH3 mole fraction in the reactor change and study the factors affecting the pollutant emission of marine diesel engine with the crank angle under different working conditions. The simulation shows that with the decrease of diesel engine speed, the maximum temperature of combustion reaction and the temperature at exhaust opening are obviously reduced. At the same time, mole fraction of NO and NH3 decreases with the decrease of rotational speed, and there is no nitride production in the combustion reaction at 25%.

Damped vibrations of cantilevered piezoelectric actuators were modeled and analyzed. The differential equations of motion derived by the extended Hamilton’s principle were a boundary-value problem with nonhomogeneous boundary conditions. An equivalent boundary-value problem with homogeneous boundary conditions was established through transformation and solved by modal analysis. Responses in time and frequency domains for unimorph and bimorph were obtained. Frequency response functions under excitations of voltage and tip force were verified by three-dimensional finite element method (FEM). Discrepancies between the analytical and FEM results were within 3%. Effects of distributed viscous damping were investigated using the analytical model. Numerical results showed that the vibration amplitude and resonant frequencies changed in opposite directions with increasing damping. This phenomenon was also reported in literature on generic cantilevers of a single material.

The total viable count (TVC) in bacon overweight can cause serious damage to human health. In order to find a rapid and nondestructive method of TVC, hyper spectral imaging technique was applied to quantitatively analysis of TVC on bacon. Comprehensively comparing the pretreatment method of multiple scattering, derivative method and so on finally the multiple scattering for pretreatment was used. And the interval optimization method of least squares model was set up to predict, and get a good prediction results. The correlation coefficient of the calibration and predictions respectively was 0.808 and 0.808, interactive authentication root mean square error was 0.115 and 0.198 respectively. Therefore, hyper spectral imaging technique combining iPLS can be used for the rapid detection of TVC on bacon.