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[Objective] Exploring the impact of hydropower development on local climate is an important guarantee for preventing and mitigating the possible negative effects of hydropower development and realizing sustainable energy development and environmental protection. [Methods] Four typical hydropower stations, Longkaikou and Guanyinyan in the middle reaches of the Jinsha River and Xiluodu and Xiangjiaba in the lower reaches of the river, were selected. By applying the climatic propensity rate, the M-K trend test, and the wavelet analysis, this study quantitatively analyzed the monthly, seasonal and yearly changes of temperature and precipitation before and after the impoundment of water in the middle and lower reaches of the river, as well as the sudden changes in the development of hydropower and the cyclical characteristics. [Results] (1) After water storage, the hydropower station had an inhibitory effect on the highest temperature and an uplifting effect on the lowest temperature in the valley. In summer and autumn, the downstream hydropower station played a cooling role, and the average monthly temperature decreased significantly in February, June, July, September, October and November, while the midstream hydropower station did not have the temperature regulation effect, with only a slight decrease in average air temperature in July. (2) After water storage, precipitation in each season increased significantly, with an increase of 0.71~27.95 mm in April, August, and September. (3) Air temperature and precipitation were related to hydropower development, and the air temperature and precipitation of the mid-and downstream hydropower stations underwent abrupt changes at different times during the development and after the water storage. (4) Air temperature and precipitation showed similar characteristics in wavelet change period, and after water storage, local precipitation showed more significant periodicity and had a certain degree of stability. [Conclusion] At different time scales, hydropower development affected local temperature and precipitation varied across river reaches, and was constrained by multiple factors such as geographic location, the surrounding environment and water storage duration.

[Objective] The physical and chemical properties and water characteristics of substrates under different eroded microhabitats were studied to provide a theoretical basis for understanding the driving and limiting mechanisms of vegetation settlement and restoration, and to provide scientific references for the practice of vegetation reconstruction in early abandoned mining areas in the North China. [Methods] The mechanical composition, bulk density, capillary porosity, pH value, electrical conductivity, and moisture characteristics of bare slopes, rills, shallow gullies, and deposit bodies were studied, and the relationships between them were analyzed. [Results] Particle size matrices varied among different eroded microhabitats, and there were differences among different soil layers. The bulk density of the substrates in different eroded microhabitats followed the order of shallow gully>rill>bare slope>deposit body, while capillary pore size followed the order of deposit body>bare slope>shallow gully>rill. There were no significant differences in the pH value of different eroded microhabitats, but there were differences in the changes in different soil layers. Electrical conductivity followed the order of deposit body>bare slope>shallow gully>rill, and was higher in the 10—20 cm soil layer than in the 0—10 cm soil layer. The matrix moisture content and capillary water capacity of different eroded microhabitats followed the order of deposit body>bare slope>shallow gully>rill. The matrix moisture content and capillary water capacity of the bare slope and the shallow gully were the lowest on the upper slope, while they were lowest for the rill on the middle slope. [Conclusion] The substrate moisture characteristics of weathered gangue dumps were significantly affected by bulk density and capillary porosity. There were relatively more sand and medium-coarse grain particles in bare slopes and deposit bodies of weathered gangue dumps, and the moisture characteristics were superior. Bare slopes and deposit bodies can provide a safe habitat for vegetation settlement and restoration.

This article is based on a gas pipeline project in a high-altitude area to conduct quantitative analysis of engineering measures and safety assessment. Analysed the impact of soil frost heave under different conditions on pipelines, and compared the changes in pipeline stress before and after taking measures, thereby demonstrating the feasibility and treatment effect of engineering measures. Based on the commonly used technical measures in pipeline engineering, three common measures were selected for analysis: increasing pipeline wall thickness, using coarse-grained soil for replacement and filling of pipe trenches, and adding insulation to pipelines. The results show that when the wall thickness of the pipeline increases from 8.7 mm to 15.9 mm, the thickness of the insulation layer increases from 5 cm to 8 cm, and the thickness of the replacement soil layer increases from 300 mm to 500 mm, all can effectively improve pipeline deformation and reduce the maximum stress value. The effectiveness of various measures in preventing frost heave has been verified, providing a theoretical basis for the selection of key parameters such as pipe wall thickness, insulation layer thickness, and replacement thickness in pipeline design in permafrost areas.

The soil barrier factors currently present in Tuquan County, Northeast China, such as drought, waterlogging, stickiness, salt, alkalinity, and barrenness. This study chose to build a core demonstration area of 50 mu in Xinglongshan Village, Tuquan County. Seven improvement measures were adopted for soil improvement, including straw returning, alkaline amendment, desulfurization gypsum, organic fertilizer, deep tillage and deep loosening, furfural residue, and salt alkali tolerant variety screening. After adopting the above measures, the average soil pH value decreased by 0.4-0.9, the total salt content decreased by more than 10%, and the organic matter increased by more than 0.2 percentage points. The physical and chemical properties of the soil in the experimental area were significantly improved. These measures not only significantly improve the soil fertility of saline alkali farmland and increase the average grain yield by more than 15 percentage points, but also play a role in protecting farmland, thus forming a virtuous cycle.

Employees' behavior and corporate social responsibility (CSR) can affect firms’ profitability and increase the corporate economic burden. This current research endeavors to explore how business firms navigate employees' technology-driven behavior and CSR sustainable practices for tax avoidance to affect firms’ performance. This study examines how CSR sustainable practices moderate the relationship between employees' behavior and tax avoidance to achieve sustainable business performance. The study incorporated the Maximum Likelihood Estimator (MLE) for the purpose of data analysis using the structural equation modeling (SEM) technique that is suitable for this sample size. The study’s target population is employees of small and medium enterprises located in Pakistan. The study has drawn a sample of employees and applied a convenience sampling technique. The findings show that tax avoidance, employee behavior, and corporate social responsibility positively affect business firms’ performance. The results further indicate that sustainable CSR practices significantly moderate tax avoidance’s effect on business firms’ performance. However, there is no condition to identify the relationship between employee behavior and firm performance. In theory, this research contributes to the corporate strategy literature by answering how corporate social responsibility sustainable practices mediate the relationship between tax avoidance, employees' behavior, and sustainable business performance. It shows that socially responsible organizations will engage less in tax avoidance behaviors. The results exhibit that the study provides a systematic, holistic framework to attain sustainable firms’ performance. The findings' generalizability offers future direction with helpful insights for business managers and policymakers.

In today’s society, with the continuous development of China’s economy, the power industry is also growing rapidly. As an important part of the logistics distribution system, the warehousing system plays an important role in the production and operation of the entire enterprise. Therefore, effective utilization of distributed generation is of great significance for improving energy supply efficiency and reducing operating costs. This paper mainly introduces the background and application status of distributed generation technology, analyzes and discusses the research and simulation of power supply network scheduling optimization methods based on DGS structure model and DGs topology mode, and gives the corresponding solutions. After the design of the system, this paper conducts a performance test on the system to determine whether the system can operate normally. The test results show that the performance of the distributed power storage system is basically stable at more than 80% under different power storage capacities, and the power utilization efficiency is also more than 90%. This shows that the performance of the power storage system can meet the needs of users.

The fine characterization of channel sand body is a complex system engineering. The longitudinal superposition relationship of channel is complex, the sandstone thickness is thin, and the lateral changes of lithology and physical properties are obvious. It is necessary to carry out the research on the integration of processing and interpretation and seismic geology. The key technologies of seismic high-resolution pre stack and post stack inversion of medium and shallow channel sand bodies with “improved HHT point spectrum whitening” and “weak sidelobe wavelet structure” as the core and “azimuth well control inversion modeling” and “Cauchy regularization high-resolution inversion” as the core have been formed through experimental research.

Industrial production is a double-edged sword, which not only brings convenience to human beings, but also does some harm to the environment. Water pollution, especially heavy metal pollution, has become a major environmental problem. In this paper, ionization reagent was prepared and attached to cellulose to obtain Cell-IA. The cationic Cell-IA was selected to evaluate the adsorption properties of PBII. The effect of the adsorbent on the actual sewage treatment was studied and whether the adsorbent could be applied in practice was determined.

In this paper, the result based on the techniques of indoor wood adhesive of Camellia oleifera cake and manufacturing of manmade board suggests that the most appropriate condition of preparation this adhesive is that the solid content is 50%, the reaction temperature is 50 °C, the reaction time is 40min, the dosage of PF resin prepolymer accounts for 50 percent. The pH of the reaction medium is 10 and the dosage of SDBS is 1%. The proper conditions hot pressing process of PF Camellia oleifera cake adhesive for bonding plywood are the hot pressing temperature is 120 ℃, and the hot pressing time is 0.7min/mm (42 s / mm), the gluing amount is 120g/m2, and the hot pressing pressure is 1.1MPa. The average water-resistant bonding strength of the plywood prepared under this condition is 0.79mpa, which meets the requirements of class II plate in the national standard GB / T 9846.3-2004. The emission of formaldehyde is 0.38 mg / L, which meets the requirements of class E0 plate in the national standard GB 18580-2001. What’s more, the cost is the lowest among all the techniques.

In this study, the application of a two-stage inexact programming with value-at-risk (TIPV) model in water resources system planning has been developed. The TIPV method is intended to tackle the inexact parameters and the risks of economic loss. The application of case study shows that more alternatives under multiple levels of risks could be generated. The amount of water shortages and the width of system benefit intervals would decrease as the risk increases. TIPV could provide more effective information for stakeholders to recognize social policies with maximized system benefits under various risk levels.

Along with the progress of the electricity market reform, the formulation of electricity prices and the bidding in the electricity market have become hot issues. Given that electricity price contains a variety of information in the electricity market and reflects market changes, insufficient understanding of electricity prices or improper response will not only affect the revenue of power supply companies, but also have adverse effects on consumers in the downstream of the electricity market. Taking Zhejiang Province as an example, this paper uses a Multi-objective optimization based on genetic algorithm to calculate the optimal power structure of Zhejiang Province under a competitive electricity market environment and evaluate the impact of the market. The results show that as the market reduces the transaction cost of purchased power, the purchased power to Zhejiang Province has a significant positive role in power cost, stability and cleanliness. The electricity cost could be cut down by 18.3 billion yuan, which is 0.04 yuan/kWh. In terms of cleanliness and stability of electricity consumption, the competitive electricity market will also bring about benefits by 2.43% and 1.64% respectively.

Cogging torque is one of the unique problems of permanent magnet generators. Its main cause is the uneven distribution of the generator’s magnetic permeability, which directly affects the starting and running performance of the generator. The study of cogging torque suppression methods is of great significance for improving the operating stability and service life of generators. Through the analysis of the principle of cogging torque, an optimization method for the amplitude of cogging torque based on Taguchi algorithm for the two parameters of pole arc coefficient and skew angle is established. And the finite element analysis method is used to quantitatively compare the characteristic parameters of the generator model before and after the optimization by Taguchi algorithm. The results show that when the pole arc coefficient and the angle of the chute are in the optimal value at the same time, the cogging torque of the generator can be greatly reduced, and its air gap magnetic density waveform and induced electromotive force waveform are ideal, which provides a research method for the design and parameter optimization of large megawatt permanent magnet synchronous wind turbines.

In order to promote the coordination of various forms of energy resources such as electric energy, heat energy, and cold energy, and to achieve complementary and efficient use of different energy sources, a method for optimizing the allocation of the capacity of a regional comprehensive energy system that takes into account the trading of electric and thermal energy is proposed. The energy interaction costs of the system and the grid heat network are included in the total cost. The optimization goal is a multi-objective function that comprehensively considers system economics, environmental protection, reliability, and interactive power fluctuations. Based on the energy hub, the capacity of each energy supply equipment in the area is optimized. Time-sharing electricity price and typical daily system economic operation are solved by genetic algorithm. Finally, an example of a park is used to verify its effectiveness. The results show that the proposed method can effectively reduce the system cost and reasonably avoid the limitations caused by the single decision factors in the system planning stage, thus providing a reference for the actual system planning and design.

Nowadays, workability is absolutely necessary for piping concrete, which is influenced by characteristics of structure of fresh cement paste. In this paper, the movement of particles in electric field and flocculent units at different W/C were observed, and rheologic characteristics of fresh cement paste at different W/C and the pastes with naphthalene sulphonate (NS) and poly carboxylate (PC) superplasticizers were investigated using rotational viscometer (NXS-11A). It is found that at initial hydration age cement particles carry different electric quantity and electrical property; increment of W/C induces flocculent units more separated, less hysteresis loop area and lower crush point; application of superplasticizers brings much less loop area and indistinct crush point. It is concluded that 1) fresh cement paste is filled with flocculation units of different strength; 2) different units are connected with one another loosely; 3) tunnels for bleeding form in the weakest connecting area. Water can disperse flocculent units to some extent, especially for superplasticizers. However, the latter can’t separate flocculation of cement particles completely.

In this work, the g-C3N4/V2C MXene composite catalyst was prepared by solvothermal method, and its denitration performance under synergistic plasma (NTP) was investigated. The results showed that when the mass ratio of V2C is 3%, the denitration performance of V-CN-3-NTP is as high as 83.3%, which is 1.2 and 2.1 times that of the V2C-NTP and g-C3N4-NTP systems alone. The apparent morphology, phase structure, and catalytic mechanism of the catalyst were studied by SEM, TEM, XRD, FTIR, XPS, etc. The results showed that g-C3N4 grows well on V2C mxene. V2C is not only an electron acceptor but also an active site for NO adsorption. The electrons and holes generated by V2C could be effectively separated by the high-voltage electric field, which improves the denitration performance and shows a good synergistic effect.

In this paper, we prepared a polyvinyl alcohol-polyethylene (PVA-Co-PE) composite nanofiber membrane catalyst decorated by Fe-MOFs/SiC and completed the photocatalytic reduction of CO2 performance. The results show that the CO2 conversion rate of composite film materials under visible light irradiation is increased by 31 times compared with powdered Fe-MOFs/SiC materials. Through SEM, XRD, BET, FTIR, DRS and other characterization methods, the influencing factors of the photocatalytic CO2 reduction process of the composite nanofiber membrane were investigated. The synergistic effect of Fe-MOFs/SiC and nanofiber membrane photocatalysis is beneficial to electron-hole pairs. The effective separation and strong absorption in the visible light region make it exhibit excellent photocatalytic activity in the photocatalytic CO2 reduction reaction.

Through the simulation analysis of the settlement and deformation law of the surface buildings caused by the construction of the biased tunnel, the following points are obtained: (1) The Peak formula is revised, and the influence range of the biased tunnel is predicted based on the formula. (2) It is concluded that when the tunnel is biased, the position of maximum deformation caused by ground settlement is generally in a parallel area 0.5 times the buried depth from the center line of the tunnel. (3) Through the double-layer verification of simulation analysis and monitoring measurement data, prior to the construction of buildings with similar weak foundations, their foundations should be reinforced in advance. (4) In the process of this simulation, the complicated influence of water pressure on tunnel excavation was not considered, which can be further optimized in the later stage.

Based on the existing engineering examples, this paper uses numerical simulation combined with the actual monitoring values on site to study the effect of the additional load on the support and the settlement of the surrounding ground, and the following conclusions are drawn: (1) When the enclosure structure is good, the settlement curve generally assumes a “spoon shape”. As the distance from the foundation pit increases, the surface settlement curve first increases and then decreases. The distance between the location of the maximum surface settlement and the foundation pit is generally half of the maximum excavation depth of the foundation pit. (2) The existence of additional load accelerates the rate of change of surface settlement, making the soil settlement from the excavation of the first layer of soil as a whole smaller than the unacted additional load to the excavation to the bottom layer as a whole larger than the unapplied load. (3) There will be a certain gap between the numerical simulation and the actual monitoring value. This gap will become larger and larger as the excavation of the foundation pit continues, but the law of change between the two is the same.

Pailou Village which is the hometown of Song Yingxing, who is the author of Tien-kung K’ai-wu, is taken as the research object in this paper. From the perspective of tourism development of traditional villages, the types of cultural resources in Pailou Village are summarized through combing the content of existing cultural resources. Then the value of its cultural resources is analyzed from three aspects: history and culture, art and society, tourism and economy. Therefore, the development path of the integration of culture and tourism is proposed, from five aspects of project positioning, industrial format, tourism planning, supporting facilities and smart tourism, the strategy of improving the tourism competitiveness of Pailou Village are summarized in this paper, which provides a theoretical reference for the sustainable development of traditional village tourism.

The composition change of microemulsion system in microemulsion flooding will inevitably cause the change of phase behavior. Microemulsion with different phase types directly affects its performance and displacement efficiency of microemulsion flooding. Therefore, in order to accurately describe this change, this paper, starting from the composition of microemulsion, gives the physicochemical properties characterization methods of microemulsion phase density, viscosity and interfacial tension, and simulates the change of physicochemical properties of microemulsion phase caused by microemulsion entering the high water-oil ratio zone in the process of flooding. The research results are of great significance for screening microemulsion systems and determining the displacement efficiency.

Significant improvement has been made in communication capability with the development of satellite communication technology, which plays a vital role in the application of power coefficient collection and transmission. The technological development of power Internet of Things contributes to the satellite resource optimization scheduling algorithm so that the requirements for satellite data of different subscribers and different priorities can be met to the maximum extent in a short period of time. Given this background, this paper proposed an optimized satellite resource scheduling algorithm that integrated family eugenics with simulated annealing.

Aiming at the problem of safe operation in the medium voltage distribution network with neutral point grounding through small resistance, the distribution network model was built, and on this basis, MW-level photovoltaic (PV) system, doubly fed Induction generator (DFIG) wind turbine, permanent magnet synchronous generator (PMSG) wind turbine and energy storage device was connected respectively in this paper. The ground current and earth potential rise was studied when the power was delivered by mistake. The simulation results show that in the system with neutral point grounding through small resistance, whether it is the traditional or the active distribution network, the three-phase power delivery method is more able to ensure the personal safety of power grid operators. However, The access to distributed generator (DG) in the distribution network will have a greater impact on ground current and earth potential rise in the case of three-phase power delivery. Especially when the ground current and earth potential rise will increase after DG connected to distribution network, which is still likely to pose a threat to personal safety and needs further research.

Designing carbon-based non-precious metal hybrid materials to replace precious metal catalysts to solve environmental pollution problems is a hot topic of research at this stage. In this work, a dual ligand Cu-MOF was synthesized by the solvothermal method and using Cu-MOF as a sacrificial template further vulcanized to obtain Cu1.96S/NSC hybrid material. The morphology and composition of Cu1.96S/NSC hybrid material were investigated by scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), x-ray diffraction (XRD), nitrogen adsorption-desorption, and x-ray photoelectron spectroscopy (XPS) in detail. Cu1.96S/NSC has excellent catalytic activity in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) showing the reaction rate constant k=0.0242 s-1, which can reach nearly 100% conversion rate in 3 min. Finally, the mechanism of Cu1.96S/NSC hybrid material’s efficient catalytic reduction of 4-NP was deeply explored.

Blockchain technology was invented for bitcoin. It serves as a new computing paradigm with a decentralized framework. For its characteristics such as decentralization, tamper-proofing, and traceability, this technology has been widely used in various industry sectors. Currently, the power industry, as China's basic energy industry, is closely linked to national economic development. In the power industry, power data storage and dispatching are of paramount importance. However, there are some security problems with traditional storage methods. Given this, this paper proposed a blockchain-based power data storage scheme, to enhance the security of power data storage.

This paper briefly summarizes that during the depressurization operation in subsea pipeline for maintenance or prevention of hydrate formation, because the flare knock-out drum pump is designed for ambient temperature, and cannot deal with the low temperature fluid in the depressurization process. Therefore, the low temperature fluid needs to be heated in the knock-out drum to meet the temperature requirement of pump. In order to avoid the volume of low temperature fluid exceeding the surge volume of the flare knock-out drum, the concept of multi stage depressurization is innovatively proposed in this paper, which meets both the requirements of pump temperature and the surge volume of flare drum. Taking a gas field project in the South China Sea as an example, the simulation analysis of depressurization temperature and pressure is carried out by using different size of the blowdown valve. It provides a good reference for the similar project in future.

In this paper, the Generalized Matching Law of electromagnetic parameters was given for in the application of radar absorbing materials, and applied in the research of absorbing properties of multi -coated absorbing materials. We gave the power reflection formula, defined the constant of general matching law M, and discussed the relationship of general matching constant M with power reflectivity RP, thickness d, relative permittivity εr, relative permeability μr. We found that the enhancement of RP was not obvious at the ε″r was optimized, but the μ″r was primary. In short, this is consistent with panorama analysis method.

The most important problems encountered in the design and operation of oil pipelines in permafrost regions are frost heaving and thawing settlement. In this paper, we conducted an investigation and analysis on the status of freezing damage of the operating oil pipelines. Based on the investigation and research, we calculated the temperature field of the oil pipeline and analysed the thawing ability under the conditions of the strain criterion. Finally, we proposed a design method for pipeline insulation and the maximum amount of thawing displacement that the pipeline can withstand. It has certain guiding significance for the thermal insulation design of oil pipelines in permafrost regions.

In this paper, we used the CASSCF/CASPT2 method to study the low-lying electronic states of the HOSS and HSSO radicals. Based on the Cs and C1 symmetries, the geometrical parameters, total energies, configurations, oscillator strengths, excitation energies, oscillator strengths and harmonic vibrational frequencies of the HOSS and HSSO radicals were calculated. We found that the ground state of HSSO radical with C1 symmetry has multi-configurational character, which leads to a significant difference of dihedral angles of HSSO radical among at our work and at References. Moreover, a transition state was given out in the pathway for the reaction from HOSS to HSSO. This transition state produces relatively high-energy barrier of 30.5 Kcal/mol corresponding to the gradual changes of the S2-H-O angle.

Reinforced concrete is needed in houses, tunnels, garden facilities and so on. The first requirement for buildings is safety. Therefore, no matter what the design concept of buildings and how the structure of buildings changes, concrete as a basic material is indispensable, and it is particularly important to pay attention to the safety of reinforced concrete building structures. Thus, the reinforcement technology of reinforced concrete is derived. In this paper, the method of strength detection of concrete building structure is given first, and on this basis, the reinforcement technology of concrete and soil is deeply studied.

The pipelines made by alloy 35CrMo are widely used in the process of flue gas injection. Therefore, corrosion behaviours of alloy 35CrMo have been investigated at varied temperatures, namely 120 °C, 150 °C, 200 °C and 250 °C, with same experimental pressure of 9 MPa and flus gas environment. Scanning electron microscopy was employed to examine the morphologies and microstructures of the oxide films. The results indicated that moderate temperature stands an essential role in the reaction mechanism and aggressive effects. In addition to increase in the diffusion rate of both alloy ions and corrosive gas, temperature can also reform the morphology of oxides by resulting in larger oxide particles and thicker oxide films, plus the transmission from needle-like oxides to spherical oxides.

Shrink-swell soils are characterized by significant volume expansions and contractions during wetting and drying processes, respectively. Railroads on shrink-swell soils are subjected to huge solicitations associated with the volume change of the soil. The highly permeable ballast layer exacerbates soil volume changes due to moisture variation, which generally lead to unacceptable uneven settlement. The mechanism behind the observed railroads problems on expansive soils, and the associated (possible) remedial solutions, are still unclear. A site in Texas has been chosen recently to study in detail the aforementioned problems. In this paper, the typical geomechanical problems associated with railroads on shrink-swell soils in Texas are discussed. We also presented the test site information and preliminary lab tests to obtain water retention curve of the site soils.