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Electric power resources is directly related to the national development and social people’s livelihood of the energy industry, is to support the future economic transformation and improve the residents living standards of rigid demand, however, the power industry is the highest carbon dioxide emissions in China, the power industry accounts for the energy industry of carbon dioxide emissions more than 40%. Under the background of the increasing demand for power resources in the current social development, the carbon dioxide emissions of the power industry are directly related to whether China can achieve the goal of reaching the national carbon emission peak by 2030. The article will summarize the driving factors of carbon emission reduction in the power industry through scenario analysis, combining the social electricity demand, power structure adjustment and the coal consumption of power generation standards, and improve the new energy generation technologies such as offshore wind power and hydropower to achieve the carbon emission of the power industry to reach the carbon peak standard. The article mainly achieves carbon emission reduction in the power industry through offshore wind power and distributed photovoltaic technologies, optimizes the power supply structure, and achieves the carbon peak target by 2030.

Lithium batteries, as the most closely watched secondary batteries, exhibit outstanding performance. Nonetheless, the formation of lithium dendrites significantly compromises their safety and hampers further development. To mitigate the impact of lithium dendrites on batteries, solid-state lithium batteries have emerged, with solid electrolytes being of paramount importance. Traditional solid electrolytes are categorized into polymers, oxides, and sulfides. However, the inherent limitations of these materials impede their effectiveness. This study proposes a novel solid electrolyte consisting of organic and inorganic materials, aiming to harness the collective benefits of the two electrolyte types to improve the electrochemical performance of solid electrolytes. Empirical data from experiments on composite solid electrolytes, incorporating polyethylene oxide (PEO) with Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and Li10GeP2S12 (LGPS), reveal that these organic-inorganic composite solid electrolytes exhibit high ionic conductivity, reduced interface impedance, and an extensive electrochemical window. It demonstrates that organic-inorganic composite solid electrolytes combining polymers with oxides or sulfides can integrate the advantages of both, achieving electrolyte materials with superior electrochemical performance. Finally, the existing problems are discussed, and future research trends are anticipated.

Many radioactive pollutants will be deposited inside the nuclear power plant pipelines after long-term service, which will form radioactive hot spots and increase the radiation dose rate level of operators. The ultrasonic decontamination efficiency was studied through the establishment of ultrasonic decontamination dynamic test bench, under different decontamination process parameters. It has also been applied in the engineering filed. The results show that: Ultrasonic decontamination efficiency increases with the increase of decontamination power, and the maximum decontamination efficiency of pollutants is up to 62.69%. The main reason is that the mechanical effect and cavitation effect of ultrasonic are significant with the increase of power, which is conducive to the removal of pollutants in the pipeline. When the decontamination time is 60min, the ultrasonic decontamination efficiency is more than 90%. Meanwhile, after ultrasonic decontamination of the pipeline hot spots, the contact dose rate at the pipeline hot spots is reduced by 75.20% at the highest, and the environmental dose rate is reduced by more than 90%, which reduces the collective dose level of operators working near the pipeline hot spot greatly, and ensures the health of the operators and environmental safety.

At present, Chinese renewable energy generation is growing rapidly, distributed power trading as a market-oriented means to promote the consumption of renewable energy power has attracted wide attention. It is urgent to optimize the mechanism design and build a credible and efficient trading environment to meet the needs of credibility and timeliness of large-scale multi-agent transactions. This paper first constructs a distributed power trading mechanism considering multi-subject transactions, and then elaborates the design idea of the power distributed trading platform based on blockchain technology from three aspects: total volume architecture, platform core technology and platform deployment. Finally, based on the operation of the actual power trading center in a certain region, field application verification is carried out, which proves the effectiveness and superiority of the distributed trading platform designed in this paper based on blockchain technology. The next research will continue to expand the typical model application pilot in the applicable areas to further improve the platform functions.

Anaerobic ammonia oxidation (ANAMMOX) is an efficient and low-fare biological nitrogen removal process. Nevertheless, there are still some challenges in mainstream request due to the limitations of substrate type and nitrate accumulation. At the present, anaerobic ammox combined process has been widely studied to solve the above issue. In this paper, the anammox combined processes developed in recent years are reviewed, and the process principles, pros and cons, influencing factors, process scalability, key bottlenecks in application and relevant work of the investigation group are discussed. Finally, the evolution of complex anammox process in urban domestic wastewater treatment was prospected.

As the most advanced vegetable cultivation technology adopted all over the world, tray seedling is the key link of vegetables to increase crop yield and economic benefit. As the key to the whole production process, the precision of tray seedlings is directly related to the survival rate of seeds. Combining the small scale of the domestic vegetable tray seedling industry, low level of mechanization, and low profit of sowing equipment, a tray seedling precision seeder is proposed in this paper and ADAMS software is used to carry out dynamic analysis on the main stressed parts. The results showed possible problems in the design of this type of mechanism, and possible causes were analyzed, the structure of the precision planter was optimized based on the results, and the motion performance of the seeder was improved, which is of great significance for the realization of precision seeding in an automated assembly line.

To help the transportation sector achieve the goal of the energy saving and low-carbon transformation, including highway, waterborne, urban transportation and ports. This paper sets four development scenarios to predict the carbon emission of the transportation sector in Guizhou province. Results indicate that in business-as-usual scenario, the carbon emissions show an overall upward trend; in high speed development scenario, the transportation in Guizhou province will reach a carbon peak in 2030, with a peak value of 8.76 million tons. China should actively take measures for energy saving and carbon reduction. By 2060, optimization of the energy structure contributes more carbon reduction than the optimization of transportation structure. We will promote the energy-saving and green development of China’s transportation carbon emissions.

The reduction of carbon emissions by airlines has become a crucial objective in achieving carbon neutrality. However, due to the existing benefits game between airlines and local governments, reducing carbon emissions in the air transport industry is a complex process. Previous research on reducing carbon emissions in the Chinese air transport industry has been divided on which approach to take. This study investigates the potential contribution of a carbon trading mechanism towards carbon emission reduction. Firstly, evolutionary game theory is employed to analyze the complex interactions between local governments and airlines, with the public will being introduced as a constraint in the proposed model. Secondly, the impact of the carbon trading mechanism on the dynamic evolution process and stakeholders is analyzed. Furthermore, the stability of the proposed evolutionary game model is verified through empirical analysis. The results show that the carbon trading mechanism plays a significant positive role in promoting both parties’ objectives, indicating that it is a feasible method for reducing emissions in China’s air transport industry.

In southeast China, slope with completely decomposed granite (CDG) soil is susceptible to landslide under heavy rainfall, due to the fissure-rich and slaking characteristics of this kind of soil. In this context, this study attempted to hydraulically improve the CDG soil in a low-carbon manner by using the composite of xanthan gum and guar gum (i.e., two different microbial biopolymers), as an alternative to cement. Hydraulic conductivity of the treated soil was measured using a tailer-made apparatus. Test result shows that the biopolymer content of 2% could lower the conductivity by over 1000 times, and the ratio of 1:1 between Xanthan and guar gums yielded the best performance in general. Application of composite biopolymer to the slope with weathered granitic soil was investigated using the finite element method simulation. Numerical result indicates that the treatment can eliminate the slope failure effectively under rainfall with a hundred-year return period.

The overlying strata of the stope can be divided into low ( immediate roof ), medium and high strata according to the degree of influence of the mine pressure behavior of the working face. Among them, the pressure step distance of low rock strata can be judged according to the roof pressure appearance of hydraulic support, and the middle and high rock strata can not be accurately and intuitively determined only by theoretical calculation. Therefore, IMU is used to monitor the motion state and fracture distance of different layers, so as to study the relationship between them and periodic weighting. Firstly, the accuracy of monitoring effect and the error of monitoring data are determined by indoor test. Then, taking the 52507 working face of Daliuta as the engineering background, 3DEC software is used to assist the verification. The research shows that the IMU monitoring data meets the requirements of error and accuracy, and can accurately monitor the rock movement ; the movement period of rock strata at different heights is different. As the height of rock strata increases, the displacement distance of rock strata gradually increases, and the median rock strata play a key role in the movement of overlying rock strata. The periodic pressure monitored is twice the actual periodic pressure.

This paper uses the Long-range Energy Alternatives Planning(leap) system model to predict the carbon dioxide emissions of the power industry and calculate the carbon peak platform period of the power industry in Guangxi, which is based on the development status of the power industry and the energy and power development plan in Guangxi during the "14th Five-Year Plan". The results show that the power structure of Guangxi is at an excellent level in the country. In 2021, the installed proportion of clean energy is 55.1% (the national average level of 44.7% in 2020), and the proportion of thermal power generation is 55.7% (the national average level of 68.5% in 2020). With the strong economic recovery , the demand for electricity in Guangxi will continue to increase. By 2025 and 2030, the electricity consumption of the whole society will reach 2.9 ×1012 kW•h and 3.7×1012 kW•h, respectively, with an average annual growth rate of about 7.1% and 5.3%. The installed power generation capacity will reach 9.4 ×107 kW and 1.5 ×108 kW, respectively. The power generation will reach 3.0 ×1012 kW•h and 4.2×1012 kW•h electricity, respectively. However, Due to the influence of resource endowment, meteorological conditions, energy storage technology and other constraints on non-fossil energy power generation, it is difficult to achieve large-scale replacement of traditional energy power generation in a short term. It is estimated that coal power production will account for 45% and 30% of the total power generation respectively in Guangxi by 2025 and 2030. Coal power will continue to be the main provider of power security for a long time in the future. Therefore, according to the current situation of power development planning, it is estimated that the carbon emission of Guangxi will reach 9.2×107 t by 2030. The carbon peak platform period of power generation industry will appear in 2029 to 2032, with a peak value of 1.1 × 108 t.

The traditional method of hydrology and water conservancy calculation is based on the assumption of natural runoff, while the applicability of method has weakened in the urbanization-affected river basins. The paper carried out research on hydrological calculation model of flood control in the middle and lower reaches of the Chuhe River under the background of urbanization. On the basis of the analysis of flood characteristics in river basins, the hydrological calculation model framework of flood control in the middle and lower reaches of the Chuhe River is constructed, which includes five modules: design rainstorm calculation, runoff calculation, regional flow concentration calculation, river-network confluence calculation and lake-reservoir regulation calculation. The parameters of runoff generation, overland flow concentration, hilly area flow concentration and river-network confluence are determined. Process simulation of the flood water levels and discharges in the middle and lower reaches of the Chuhe River in 1991 and 2008, which are the years with heavy rains, is conducted. The flood simulation of June 1991 shows that the error of water level is -1cm ~ + 8cm, and the error of discharge is +26 m3/s. The flood simulation of August 2008 shows that the error of water level is -8cm ~ + 2cm, and the error of discharge is -9 m3/s. The overall simulation results are relatively stable with all the calculation errors within the allowable range, and the results fit the facts well.

The atrophy of the entrance channel in the North Branch of Changjiang Estuary and the sediment supplied by landward tidal flow from the sea to the branch, threaten the sustainable use of the numerous ports and wharves along the riversides. Four different plans of two groups to mitigate the shrinking of the North Branch were proposed and tested. The plans in the first group aimed to expand the entrance channel and the upper section of the North Branch through dredging. The purpose of the plans in the second group was to reduce the landward tidal volume in the lower section of the North Branch to reduce the sediment import from the sea. The effects of these plans were simulated by a 2D computational hydrodynamic model, and the results such as tidal volume at different sections, the portions of tidal volume in different branches, and the high and low tidal levels at the monitoring points, were obtained and compared. After that, one plan from each group was recommended. The measures of the recommended plans have been mostly adopted in the report of Revision of the Comprehensive Regulation and Development Plan of the Changjiang Estuary.

Weeds are one of the main factors affecting orchard yield, fruit quality and economic benefits. However, present methods have been lower effect and high labor intensity. To inhance the effect of weeds control on orchard, a new green and economic agent suitable for drone with choline chloride and eucalyptus oil as the main components was developed. Adopting optimized “3414” test design, the paper studied the prevention and control effect of this new weed control agent on 8 kinds of main weeds in the orchards of the Yellow-Huai Rivers. The results showed that T5 and T12 were significantly (P≤0.05) control the growth speed of 8 kinds of weeds, T4 was only inhibit the growth of Erigeron canadensis, Digitaria sanguinalis and Artemisia annua, T11 was only inhibit the growth of Tribulus terrestris, Humulus scandens and Cyperus rotundus, and T3 and T13 were promote the growth of weeds, which had the worst control effect among all treatments. Combined with the economic benefit analysis, the cost per 667m2 of weed control of T12 was 124 RMB, which was the most economical compared with manual weeding and mechanical weeding. Therefore, applying 30g choline chloride, 120 mL eucalyptus oil and 75g sucrose ester to each 667m2 is recommended to be popularized as a new green and economical weed control agent in the orchard production of the Yellow-Huai Rivers.

LIBs is a kind of energy storage device, which has the advantages of high energy density, no memory effect, good safety performance, and many cycles; It is widely used in many scientific and technological fields at home and abroad. With the large-scale increase in the use of lithium-ion batteries, the amount of scrap also increased. In order to better realize resource recovery, energy conservation and emission reduction, it is necessary to study a series of new technologies for waste battery recovery; This review mainly introduces the recovery process of the waste cathode material (LiNixCoyMn1-x-yO2) of the ternary battery, and carries out the resource recovery. The content describes the three major links of the recycling process. The first link introduces the pretreatment of waste ternary batteries. The second link analyzes the current methods of recycling the cathode materials of waste ternary batteries. After analyzing the advantages and disadvantages of each method, the process of wet recycling is introduced in detail. It is also the most commonly used way of recycling waste batteries at this stage. The last link describes the regeneration process of cathode materials.

With the gradual realization of China’s 14th Five-Year Plan, the proportion of installed renewable energy capacity in all regions has increased significantly. The access of a high proportion of renewable energy has brought serious challenges to the safe and stable operation of the power system. The uncertainty of wind power and photovoltaic output makes it difficult for the traditional reserve demand determination method to economically and effectively calculate the reserve capacity required by the system, so it is urgent to propose a reasonable reserve capacity demand determination method. On the one hand, it ensures that the deserve capacity needed by the system is sufficient to cope with real-time active fluctuations, and on the other hand, it improves the economy of the reserve capacity. The reserve demand determination method considering the different time periods uncertainty of wind and solar in this paper is able to meet the reserve demand of new power system. At last, the article proves the benefits of Reserve Demand Determination Method through a numerical example.

At present, with the vigorous development of electric vehicle industry, power battery, as an important power source of electric vehicle, has attracted more and more attention of researchers. Among many kinds of power batteries, lithium-ion battery has been widely studied by many experts and scholars because of its clean, pollution-free and other advantages. As an important part of battery management, battery energy equalization technology makes the energy in the battery pack flow between single batteries by building an equalization circuit, which provides a strong guarantee for the efficient output and stable operation of lithium-ion batteries. This paper summarizes the current equilibrium topology of lithium-ion battery pack by summarizing and combing various types of existing equilibrium structures. According to the development process of equilibrium technology, this paper introduces the working principles, advantages and disadvantages of passive equalization, active equalization and active passive hybrid equalization structure, and summarizes the design idea of current equilibrium circuit by systematically summarizing the characteristics of the development of equilibrium circuit structure in recent years, According to the latest research progress, grasp the future development direction. Finally, according to the current balanced technology development, this paper puts forward personal views and prospects for the future balanced technology development.

This paper intends to provide data as reference basis for Heilongjiang Provinces’ optimization of precipitation forecast and the resource allocation. The precipitation characteristics of Heilongjiang Province from 1954-2013 (60 years) were studied by Mann-Kendall rank order correlation test, mutation test, linear trend analysis, and Kriging interpolation combined with GIS analysis. The results show that the overall trend of precipitation in Heilongjiang Province from 1954 to 2013 was decreasing, but the results of segmental analysis show that the trend has been increasing since 1980, and the spatial distribution was characterized by high in the east and low in the west, with the precipitation center in the middle; the seasonal average precipitation gradually increased from east to west, and the precipitation was mainly concentrated in summer, accounting for 63.47% of the year. The annual precipitation was mainly light rainfall, but the difference with the medium rain was not large, both about 35%.

As a means to adjust the temperature of the thermal zones in buildings, building thermal mass is regarded as one of the essential sources of energy flexibility. It is still challenging to quantify the energy flexibility of passive thermal mass, making it oppugning to use thermal mass for buildings’ demand response (DR). A method to accurately quantify the energy flexibility from heating, ventilation, and air conditioning systems (HVAC) is important for buildings to participate in DR projects. This paper proposes a novel data-driven model to quantify HVAC’s electrical demand under dynamic global temperature adjustment. The Markov chain is first used to implement an effective sampling method to produce a global temperature resetting schedule representing different temperature resetting. Next, EnergyPlus evaluates the HVAC electrical demand under the various temperature reset scenarios. In the end, the LightGBM algorithm is used to develop the data-driven model. Having validated the proposed model, the case study was conducted in a DOE reference office building for EnergyPlus. Results demonstrate that the Markov chain outperforms the probabilistic method when sampling temperature setpoint schedules. In the future, the proposed data-driven model can be used to evaluate the flexibility capacity of an energy management system in grid-integrated buildings.

Contemporarily, large spaces prevail in many diverse and complex buildings, but meanwhile, incur more demanding requirements about thermal comfort and energy saving. Conventional building energy simulation (BES) computes the whole building based on the assumption of quiescent and uniform air. By contrast, computational fluid dynamics (CFD) can obtain rich and detailed airflow results, but consumes tremendous computational time and resources. Then, the zonal model as an intermediate method between these two models has gradually approached to the visual field of the public, which plays an important role in rapidly predicting the overall thermal stratification of large spaces. Therefore, this paper discussed a practical and automatic method of integration of the zonal model and BES. In this way, annual dynamic energy consumption of large space buildings can be analysed, which will exhibit significant potential in the engineering field, especially at primary design stage.

The energy router composed of double active bridge (DAB) can interconnect multiple voltage level AC distribution network through DC lines to form AC/DC hybrid distribution network. The fault types of the system are diverse and the fault characteristics are complex. This paper studies the fault characteristics of the system in detail. The single-phase grounding fault of AC network side and single-phase grounding fault of AC valve side occurred in the system. This paper explored the impact of the AC side of the system after the above failure, and make a detailed comparative analysis. The results show that DAB can isolate the influence of AC side fault, and provide theoretical basis for the selection of grounding mode and the design of protection system for AC/DC hybrid distribution network.

Machine-made sand was significantly different from natural sand in terms of particle gradation, morphology, composition and structure. The concrete composed of mechanical sand and natural sand was greatly influenced by the physical and chemical properties of sand and gravel in terms of its microscopic appearance and macroscopic properties. Therefore, this paper aimed to systematically analyze the big data of machine-made sand performance testing, and focus on the fluctuation of the fineness modulus, stone powder content, and other indicators of machine-made sand particles in various regions of Shaanxi, and solve measures were further discussed.

Compared with the direct access to the main power grid and diesel generators, this paper puts forward the scheme of using electric ships to shuttle between islands to transport electric energy, analyzes the limitations and defects of its application in offshore islands; and then puts forward a comprehensive energy supply system of offshore islands. The comprehensive energy supply system can make full use of the rich renewable energy of the islands, and realize the optimal allocation of the overall resources of the islands. At the same time, the energy supply system can break the isolated development pattern of island power grid and connect the island group power exchange ship. This paper analyzes the connotation and characteristics of the system, puts forward the key technology for building the integrated energy supply system of ocean island group, and gives the design and operation analysis example of power exchange ship.

Bacterial colonies detecting and counting is tedious and time-consuming work. Fortunately CNN (convolutional neural network) detection methods are effective for target detection. The bacterial colonies are a kind of small targets, which have been a difficult problem in the field of target detection technology. This paper proposes a small target enhancement detection method based on double CNNs, which can not only improve the detection accuracy, but also maintain the detection speed similar to the general detection model. The detection method uses double CNNs. The first CNN uses SSD_MOBILENET_V1 network with both target positioning and target recognition functions. The candidate targets are screened out with a low confidence threshold, which can ensure no missing detection of small targets. The second CNN obtains candidate target regions according to the first round of detection, intercepts image sub-blocks one by one, uses the MOBILENET_V1 network to filter out targets with a higher confidence threshold, which can ensure good detection of small targets. Through the two-round enhancement detection method has been transplanted to the embedded platform NVIDIA Jetson AGX Xavier, the detection accuracy of small targets is significantly improved, and the target error detection rate and missed detection rate are reduced to less than 1%.

Since the outbreak of Corona Virus Disease 2019 (COVID-19) in December 2019, more than 26 million people have been infected. Urban and rural communities are the first line of defense for epidemic prevention and control. As an effective means of disease prevention and control at the community level, health management is of great significance in how to give full play to the professional advantages of health managers at present, and in combination with the current urgent situation of lack of specific drugs and vaccines, to maintain the health and social stability of the community population to the maximum extent. By assessing and intervening the health risk factors of COVID-19, the health manager can help the community effectively control the source of covid-19 infection, cut off the transmission route of COVID-19, effectively protect the vulnerable population in the community, and thus delay the spread and spread of COVID-19.

Agricultural supply chain finance provides a feasible supply channel for the fund demand in rural economic development, alleviates the financing difficulties of small and micro enterprises and farmers in rural areas. However, there are also problems such as low standardization of agricultural products, imperfect credit risk system and incomplete information system, which seriously hinder the implementation of Rural Revitalization strategy. Financial product innovation is put forward in this paper, giving play to the role of government-led, perfect the premium subsidy, guarantees subsidy policy, actively into more involved in the main body, using the emerging technology industrialization construction, building ecological system resource sharing, expand the scope of services, to better precision power financial poverty alleviation, finally realizes the Rural Revitalization strategy.

In order to further understand the impact of industrial mining on the environment, this study conducted environmental monitoring on the radionuclide thorium content in a water body in an industrial mining area in Gansu Province, aiming to fully understand the occurrence of radioactive map elements in the area and its impact on the local. The specific impact caused by the ecological environment. The results of this paper are as follows: In the water environment surveyed this time, surface water has the highest content of radioactive thorium at 0.2μg/L, and the lowest concentration of radioactive thorium in groundwater, with an average concentration of 0.04 μg/L. And with the depth of surface water sampling, there is a negative correlation between the content of thorium in the water. This research content can provide sufficient reference materials for the occurrence of thorium in the water in industrial mining areas, and is of great significance to the related research on radioactive elements in the water.

Aiming at the question of improvement expansive soil in Nanyang area, the composite improvement method of lignin and cement was adopted. Based on the unconfined compressive strength test, the variation law of unconfined compressive strength of improved expansive soil with different lignin content, different compaction degree and different curing age was studied. The test results show that the composite of lignin and cement can effectively improve the unconfined compressive strength of expansive soil. The unconfined compressive strength of L-C (lignin and cement) improved expansive soil reaches the maximum when the cement content is fixed at 4% and the lignin content is 1%. The unconfined compressive strength of L-C improved soil increases with the increase of compaction degree and curing age, and the strength growth mainly concentrated in the first 7 days of curing age. From the point of improvement mechanism, the hydration and gelation reaction of cement occur in expansive soil, and gel material with higher strength is formed to enhance the strength of expansive soil. The appropriate amount of lignin can fill the pores between soil particles and make the connection between soil particles more closely, so as to improve the strength of expansive soil.

This article adopts the way of progressive transformation of edge calculation and the combination of the substation, this paper makes a brief introduction to the calculation of edge, and describes its development situation at home and abroad, and then stand for intelligent SCADA system on 750 kV substation briefly, the architecture will eventually margin calculation and combination of SCADA system, discuss the practicability of EC SCADA system.

Because of the problem of local scour caused by the change of the flow structure caused by the water-resistance of the column bridge pier, the theoretical analysis, and indoor water tank test were used to study the effect of installing a new anti-scouring device in front of the bridge pier on the local scour reduction effect; the influence of the main design parameters such as the height of the protective device, the angle of the protective device and the distance from the protective device to the bridge pier on the local scour of the bridge pier was selected, and the optimal parameter design combination was selected. The test results show that: under the same water flow conditions, the maximum scour depth reduction rate of the measuring point under the protection of the protective device is 48.4% to 74.2% compared with the unprotected scour; the reduction rate of the bridge pier is relative to the relative height of the device and the device equivalent. The angle and the distance between the device and the bridge pier are related, and the shock reduction rate decreases with the increase of the flow intensity. In the test range, the ratio of the device height to the water depth is 2/3, the device angle is 60 °, and the distance from the bridge pier is 3. When the diameter of the pier is doubled, the effect of reducing the impact on the pier is the best.

To improve the power generation of microbial fuel cell (MFC), the cathode is modified to increase its oxygen reduction reaction (ORR) activity by using Co/UiO-66, which derived from pyrolyzing the mixture of Co(NO3)2 as the metal precursor incorporated with NH2-UiO-66. It was found that Co/UiO-66 (MOF-900) has been developed as a high-performance electrocatalyst for ORR at a pyrolysis temperature of 900 °C. Therefore, Co/UiO-66 should be a promising oxygen reduction catalyst for application in MFCs. This study provides technical and theoretical validation for the MFC performance improvement by ORR active MOF-derived catalysts modified cathodes.

Pueraria lobata is a traditional plant used for both medicine and food. Pueraria starch has a long history of folk consumption in China. The processing of pueraria starch produces a lot of waste water and is often discarded, but it contains rich nutrients and is suitable for the growth of microorganisms. In this study, pueraria starch processing wastewater was used as a new fermentation substrate for kombucha fungus to develop a new functional beverage. After 8 days of static fermentation in 28 °C, the pH of kombucha fermented with pueraria starch processing wastewater as substrate decreased to 2.78, the total acid concentration was 0.158 mol/L, and the mass concentration of reducing sugar decreased to 2.05 mg/mL. The pueraria starch production wastewater before and after fermentation was extracted with 80% methanol and the mass concentration of total flavonoids was determined. The antioxidant activity of pueraria starch processing wastewater before and after fermentation was analyzed by using three antioxidant models: DPPH free radical scavenging ability, ABTS cationic free radical scavenging ability and ferrous ion reducing power. The results showed that after 7 days of fermentation, the mass concentration of total flavonoids in kombucha produced by the pueraria starch processing wastewater was 268.45 mg/L. The antioxidant activity of fermented kombucha beverage was significantly higher than that of unfermented pueraria starch processing wastewater. This study provides a new way for the resource utilization of Pueraria starch processing wastewater.

In UHVDC transmission system, the inverter station is located in different geographical locations, and there are two sections of lines in single pole of HVDC system, which brings challenges to the traditional closed line protection. In this paper, firstly, the structural characteristics of series connection mode and the output characteristics of each converter in case of line fault are analysed, and the adaptability of conventional line protection in series multiple receiving ends system is studied. According to the characteristics of UHVDC system with multiple receiving ends in series connection mode, a hierarchical protection strategy is proposed and verified in PSCAD model.

Lithium ion capacitors with liquid electrolyte are prone to leakage, combustion, explosion and other dangerous accidents. To solve these problems, the solid gel separator prepared by polyvinylidene fluoride - six fluoropropene (PVDF-HFP) is used in this work to improve the safety and stability of lithium ion supercapacitors. The PVDF-HFP based gel separator was used to replace the commercial separator and electrolyte in the lithium ion capacitor. The solid-state lithium ion supercapacitor was matched with porous carbon (PC) and hard carbon (HC). The maximum energy density of the device is 148.76 wh/kg, even at the power density of 33.6 kW/kg, which still retains 20.6 wh/kg. In addition, 83.3% capacity of solid-state lithium-ion supercapacitor is retained after 8000 times of charge and discharge. The requirements of high power energy density, high cycle stability and high safety are realized.

In order to study the mechanical properties of the joints, ANSYS software was used to simulate and analyse the failure form, ultimate bearing capacity, load-displacement curve and the rotational stiffness of the wheel-coupler joint node under force. Results: The wheel-coupler joint node has obvious non-linear characteristics when subjected to force; The bilateral symmetric tension and compression state could better reflect the failure form and deformation of the joint; The rotational stiffness of the wheel-coupler joint node under tension and bending was greater than that under bending and torsion, and was greater than that under tension, bending and torsion.

Formation sampling while drilling (FSWD) is one of the most advanced formation sampling techniques in the world. It is characterized by short operation time, shallow mud invasion, and the obtained formation data is closer to the real situation of the reservoir. During the sampling process, the first fluid that the suction probe on the borehole wall inhales is basically drilling mud filtrate. With the increase of suction time, it gradually mixes into the formation fluid, and finally the formation fluid is infinitely close to 100%. At this time, it is very important to judge the starting time of sampling. If the sampling time is too early, the percentage of samples contaminated by drilling filtrate will be higher, which can not meet the requirement of fidelity. If the sampling time is too late, the drilling fluid will stop circulating for too long, which will cause sticking. In this paper, the prediction method of sampling time is to simulate the permeability of drilling fluid to formation under certain formation parameters and drilling conditions. Based on the simulated permeability results, the suction model of sampling tool is established to simulate the pumping situation, and the variation of the content of drilling filtrate in the pumped fluid with the suction time is obtained, that is, the relationship between the contamination rate of formation fluid and the suction time, This method is of great significance to the field application of fluid sampling tools while drilling.

The underground coal gasification (UCG) technology is basically mature, but the influence of its own process and tools slows down its industrialization progress. This paper introduced the development and field test of two new UCG coiled-tubing gasification agent injection tools. The test results show that the two kinds of gasification agent injection tools ensure the injection point under control by conducting downhole temperature measurement and ground monitoring jointly. The problem that the tool is burnt by the backfire is solved by designing a backfire prevention device. To realize low pressure drop, the gasification agent flow channel inside the tool is designed optimally to keep the tool pressure drop not more than 0.5 MPa and the system pressure drop not more than 3 MPa. The tool overall has the characteristics of low pressure drop, high temperature resistance, backfire prevention and anti burning to satisfy the demand of the field test. This technology is a new achievement in the development of UCG technology and equipment in China. The research conclusions can provide technical reference for developing a new generation of UCG technology.

The structure and form of modern power grids are becoming more and more complex, and there are many indicators and factors that need to be considered to evaluate the development status of the power grid. In order to diagnose the development level of power grid, the index system is reconstructed, which includes seven dimensions: the coordination of power grid development speed, the coordination of power grid development scale, the coordination of power grid structure, the security and reliability of power grid, the level of equipment, the utilization efficiency of power grid and the development benefit of power grid, the construction principle and index selection basis are given. When dealing with contradictory problems in reality, methods combining quantitative and qualitative can be applied to study. The matter element analysis method is applied to power grid development diagnosis, and a model of power grid development diagnosis based on matter element analysis is established, the model can not only diagnose the development level of power grid, but also determine the key factors that affect the diagnosis results, and give suggestions for improvement. The practical example verifies the feasibility and rationality of the method, which has good evaluation accuracy and prediction effect.

Advanced oxidation technology is attracting attention as an effective method of water treatment that can degrade various organic pollutants. The combination of photocatalysis (UV) and ozone (O3) and titanium dioxide (TiO2) is a promising advanced oxidation technology. The combination of ozone, hydrogen peroxide, ultraviolet light and other oxidants for catalytic oxidation is also the current mainstream advanced oxidation technology. They can effectively degrade emerging water pollutants and alleviate water pollution problems. Titanium dioxide, hydrogen peroxide, and ozone are all popular catalysts because of their low cost, non-toxicity, strong oxidizing ability, and easy contact with various surfaces.

In this study, an integrated ecological system was constructed to treat small scattered aquaculture wastewater in southern rural areas of China. The water outlet of 4 level wetlands was continuously monitored from July to December in 2017. Results showed the average concentrations of total nitrogen (TN), ammonia nitrogen (NH4+-N), nitrate nitrogen (NO3-N), total phosphorus (TP) and chemical oxygen demand (COD) were 43.64mg/L, 17.53mg/L, 1.71mg/L, 1.66mg/L and 51.39mg/L in the average effluent concentration of grade I wetland, respectively, and 8.35mg/L, 4.42mg/L, 0.24mg/L, 0.26mg/L, 21.32mg/L in the average effluent concentration of grade IV wetland, respectively. The removal rates were 81%, 75%, 86%, 85% and 59% for TN, NH4+-N, NO3-N, TP and COD in the integrated ecological system, respectively. The effluents from the integrated ecological system met the requirements of “Discharge Standard of Pollutants for Livestock and Poultry Breeding” (GB 18596-2001) and achieved “Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant” (GB 18918-2002) the center two levels to discharge the standard. Obviously, the integrated ecological system could work efficiently in treating the rural scattered aquaculture wastewater, and also possess merits of low construction and operation costs and simple management method, which will be benefited to its application in the southern rural regions of China.

Taking a large grid frame in a maintenance hangar of Guangzhou Baiyun Airport as the research object, the construction steps of lifting the grid structure are briefly described, and the static mechanical characteristics, dynamic mechanical characteristics and stability of the large grid frame were studied by using Midas/Civil finite element analysis software, which meets the design and the practical application requirements. Since its first six orders safety factors are greater than 4. The stress state of the nodes at the important supports in the grid is mainly controlled by axial force.

Veterinary drugs originally used to diagnose, prevent, control and treat animal diseases. However, now some of them can also be mixed into livestock feed as growth promoters. Although most countries have specified animal-derived veterinary drug residue standards, such as the maximum residue limit, withdrawal period and prohibition of some veterinary drugs as growth promoters, there are still some animal-derived products with illegal amount of drug residues. Consequently, long-term intake of products with excessive residues will result in irreversible impacts on human health, livestock industries and natural environment. To minimize these risks, the techniques of drug residues detection plays an important role in guarding food safety of animal products. Moreover, Veterinary drug residue detection technology, according to the author's opinion, can be divided into instrumental method, immunoassay method, biomolecular technology and bio-sensor technology. The purpose of this article is to collect and summarize the existing journal literature current about status, hazards and detection techniques of animal-origin veterinary drug residues so that ordinary readers can briefly understand the research status of the residue detection techniques, farmers can understand the importance of regulating and suitable handling of veterinary drugs, and relevant researchers may know about the emphasized difficulties that need to be overcome in drug residue detection techniques.

In the context of the increasingly severe global greenhouse effect, the “14th Five-Year Plan” proposes to “promote green development and promote harmonious coexistence between man and nature”, which provides a new platform for the faster and better development of low-carbon countries. The low-carbon economy has entered a high-quality stage of China’s economic development in the new era, which is of great significance to the overall green transformation of China’s economic and social development. In order to assess the development level of China’s low-carbon economy, this paper estimates the carbon emissions and carbon emission intensity of energy consumption from 2008 to 2017 and applies the LMDI model to decompose the influencing factors of carbon emissions, analyzes the contribution rate of driving factors, and proposes energy saving, emission reduction and low carbon. Developmental countermeasures. The results show that economic growth and energy intensity are the biggest driving factors for promoting and suppressing carbon emissions, respectively. Measures are taken to improve energy structure, increase utilization efficiency, develop low-carbon industries, and promote low-carbon life.

Consolidation and permeability tests were conducted on soft clays with different liquid limit by GDS consolidation apparatus. Some fitting parameters were studied for 4 common nonlinear permeability models based on the test data. But different soil samples have different parameters for the same model. In order to find the universal law of permeability coefficient and compressibility with the soil property and void ratio, the void ratio was normalized by the liquid void ratio eL, and the relationship of e/eL with logkv and logp were established based on the test data. The Chapman-Richard curve fitting model was adopted to best fit the obtained time-compression data. The relationship between e/eL with logkv was further verified using 30 groups of test data of permeability collected from China and abroad. The relationship between e/eL with logp was also discussed in this paper, and the fitted curves and nonlinear equations was further simplified into two linear equations at the point of e/eL=0.9 so as to consistent with the well-known theory. The nonlinear equations can be used to calculate the permeability and compressibility according to the void ratio and liquid limit.

In view of the demand of 800 meters Super Long Span CFST arch bridge, the composite bridge of CFST flying swallow arch and self-anchored suspension cable is proposed. The thrust of flying-bird CFST arch bridge and the tension of self-anchored suspension bridge are balanced, forming a self-balanced structure system. The arch rib structure is mainly stressed, supplemented by the self-anchored suspension system, which works together and has complementary advantages. Using the single leaf hyperboloid variable section steel tube four limb space truss arch rib structure, the self-weight of the mid span arch rib section structure is reduced, the risk of construction and hoisting of the mid span section is reduced, the section size at the arch foot is increased, the mass center and stiffness center of the arch bridge structure are effectively reduced, and the stability of the super long span concrete-filled steel tube arch bridge is increased. Combined with the actual project, the parameters are designed, the Midas finite element model is established, the internal force analysis and calculation, modal analysis and buckling analysis are carried out, and the superiority of the structural technical measures is verified.

Combined with the engineering background of a 5000-meter Strait Suspension Bridge, the configuration study of the hyperbolic parabolic space cable suspension bridge was carried out, and the ANSYS finite element analysis model was established to analyze and study the structural internal force and dynamic modal characteristics. The research shows that the hyperbolic parabolic space mixed cable suspension bridge has excellent spatial stiffness and wind stability performance, its torsional frequency and torsional frequency ratio are significantly improved, the critical wind speed of flutter is greatly improved. In order to further improve the wind stability of the hyperbolic parabolic space mixed cable suspension bridge, temporary wind resistance cable measures adopted during strong typhoons are proposed. This method can ensure that the 5000-meter-level hyperbolic parabolic space mixed cable suspension bridge has the ability to withstand 120 m / s rare extreme typhoons.

We calculated the area of seven ecosystems, used the NDVI index to analyze the temporal-change of vegetation-covered land in the Qinghai Lake basin from 2004 to 2019, and the principal component analysis to analyze the driving mechanism of desertification. The results showed that grasslands are the dominant ecosystem, and the desert ecosystem had an area of 32 km2, accounting for only 0.1% of the total area. The evolution of desertification was in the reversal stage. The vegetation cover increased from 54% in 2004 to 66% in 2019, showing a change process of mild destruction-slow restoration: 2004-2008, high degree vegetation-covered land dominated the declination of vegetation with the dynamic trend of -5.67%; 2009-2013, medium degree vegetation-covered land dominated the restoration of vegetation with the dynamic trend of 2.45%; 2014-2019, medium and high degree vegetation-covered land showed an increasing trend with the dynamic trend of 0.86% and 1.17% respectively. Natural and human factors, which were manifested as the domination of human activities and the exacerbation effect of natural factors, influenced desertification. The first principal component integrated both anthropogenic and natural factors accounted for 52.27% of the contribution rate, while the second principal component included only natural factors that accounted for 23.77%.

At the beginning of 2020, the Covid-19 epidemic broke out and soon became a global public health problem. Therefore, many countries are speeding up the development of antiviral drugs and COVID-19 vaccines to achieve effective prevention, control, and treatment of Covid-19. This paper reviews the pathogenic mechanism and detection and diagnosis of COVID-19 and the status and research progress of antiviral drugs, vaccines, and some other treatments against it based on previous articles published in this field. Although Covid-19’s pathogenic mechanism has been generally figured out and the detection methods are advanced, old pneumonia treatment methods are adopted Covid-19 due to the lack of high-efficiency antiviral drugs. Meanwhile, as more and more safe and effective vaccines enter the clinical phase, the treatment of the Covid-19 epidemic may rely more on the prevention-oriented strategy.

With the large-scale renewable energy grid integration, the problems of traditional transmission network planning methods, such as high investment, low utilization rate and difficulty in implementation, have gradually emerged. Therefore, in order to improve the level of new energy consumption, effectively improve the operation efficiency of power grid and optimize the investment benefit, this paper proposes a new mode of power grid planning based on adjustable integrated resources. This paper focuses on two key planning methods: new energy confidence capacity assessment methods and load forecasting methods considering demand side resources.Then the paper takes a city-level 220 KV power grid as an example, applies a new power grid planning method to carry out planning, and verifies the effectiveness of the proposed planning model and method.

This paper takes the ultra-low permeability sandstone reservoir of Jingbian oilfield in Ordos Basin as the research object, analyzes the petrological characteristics, diagenesis, physical characteristics and pore structure characteristics of the reservoir, and carries out reservoir sensitivity evaluation by using rock casting thin sections, X-ray diffraction, and sensitive flow experiments. The research results show that the ultra-low permeability Chang 6 sandstone reservoir has weak velocity sensitivity, medium-weak water sensitivity, weak salt sensitivity, weak alkali sensitivity and strong acid sensitivity; the damage mechanism of reservoir sensitivity mainly depends on the composition of clay minerals and pore structure after diagenesis. The clay mineral content from high to low is chlorite, illite, a small amount of illite / smectite layer, and kaolinite, of which the chlorite content is as high as 75 %; the reservoir has poor physical properties, the types of small hole-thin throat and small hole-fine throat. The reservoir is prone to blockage such as bridge plugging. Therefore, ultra-low permeability sandstone reservoirs are prone to different degrees of sensitivity. The reservoir characteristics are consistent with the reservoir sensitivity evaluation results.