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Building on successful development experience of transformation induced plasticity (TRIP) steels, an analogous concept was taken to design high performance titanium alloys. This article describes a computational design framework of novel near-α TRIP titanium alloys with both high yield strength and fracture toughness for naval structural applications using a systems design approach integrating processing/structure/properties/performance relations. Predictive models including a transformation stability model based on Olson-Cohen heterogeneous martensite nucleation theory for titanium alloys was proposed. Integration of the models with CALPHAD software and databases enables parametric design optimization to meet design objectives. The developed models were calibrated with experimental measurements.

With the continuous development of industry, the emission of volatile organic compounds (VOCs) continues to increase, and the pollution problem becomes increasingly serious. For example, in industrial production processes such as papermaking and traditional Chinese medicine extraction, low-content and complex volatile organic compounds will be produced, which will affect the factory environment. This article introduces the development and research status of VOCs sampling and treatment technology in recent years, explains the advantages and disadvantages of adsorption method, absorption method, membrane separation method, catalytic combustion method, biodegradation method, and low-temperature plasma technology application, and looks forward to the future development trends in this field.

In contemporary society, the escalating anxiety among college students has emerged as a pressing social concern, impacting both their mental well-being and academic performance by influencing levels of learning motivation. This research posits a negative correlation between the burgeoning learning anxiety and the motivation to learn among college students. Employing a quantitative research approach, data is gathered through structured questionnaires, and subsequent analysis is conducted using SPSS statistical software to derive meaningful insights. The study primarily focuses on Chinese college students, aiming to unveil the intricate relationship between learning anxiety and motivation. Through this investigation, the researchers seek to formulate strategies that mitigate learning anxiety and concurrently bolster intrinsic motivation for sustained learning among Chinese college students. This research serves as a key step in understanding and addressing the contemporary challenges associated with the mental health and academic performance of college students, paving the way for interventions that foster a positive learning environment.

The post-combustion chemical decarbonization process is one of the key technology selections for the low-carbon development of natural gas power plants. The high energy consumption of amine regeneration is hindering its commercial application. In this paper, two new mixed amines solvent 15%Diethylaminoethanol (DEEA) +9% Piperazine (PZ)+ 6% Monoethanolamine (MEA) named DT01-3 and 22% 1,4-butanediamine (BDA)+ 4% N-Methyldiethanolamine (MDEA) + 4% 2-Amino-2-methyl-1-propanol (AMP) named DT02-2 are verified by the 3000Nm3/h industrial demonstration system. The steady state condition was gradually established by adjusting the main parameters such as flue gas flow rate, absorber inlet flue gas temperature, solvent circulation flow rate, regeneration tower operation pressure, steam flow rate and so on with the goal of maintaining ≥90% of the capture efficiency. The results show that the CO2 capture efficiency of DT01-3 and DT02-2 is 91.23% and 90.81% respectively. The regeneration heat consumption is 3.65 GJ/tCO2 and 3.73 GJ/tCO2. The amines consumption is 0.95kg/tCO2,1.1kg/tCO2. The operating cost of DT01-3 and DT02-2 is 336.37 CNY/t,346.04 CNY/t, which is 20.94%,18.68% lower compared with MEA.

Understanding the transformation mechanisms of surface water and groundwater positively impacts the rational utilization of water resources and the more scientific allocation of their uses. Many factors affect surface water and groundwater interaction (SGWI), among which river runoff is the most critical variable. Studying the response mechanism of SGWI under changes in river channel volume can help understand the essence of SGWI. Using the Taoer River alluvial fan as the research area, daily runoff data from hydrological stations in the study area from January to March 1961, 1971, 1981, 1991, 2001, and 2011 were collected. The daily SGWI was calculated using the water balance and flow speed difference methods. The results show that river runoff is the main factor controlling the SGWI, and the interaction quantity (IQ) is more stable when the IQ is relatively small.

Starting from the market rules of the pilot provinces of the domestic spot market, this paper analyzes the mechanism of market intervention and suspension, the mechanism of the power supply period, and the mechanism of market clearing anomaly. At the same time, combined with the real-time operation of the Inner Mongolia power grid, the traditional dispatching mode and the power spot market operation dispatching mode are compared. Given the abnormal frequency, section overload, and insufficient spinning reserve in real-time operation, an auxiliary decision mechanism of manual intervention in the power spot market is proposed. The mechanism includes load bias setting, section limit bias setting, deviation monitoring, and other auxiliary functions, which provide a method of quick intervention under the electric spot market to ensure the safe and stable operation of the power grid.

Objective To elucidate the synergistic mechanism of Liuwei Dihuang Pills (LWDHP), with multi-components, multi-targets and multi-channels in the treatment of senile dementia. Methods We searched Chinese and English databases to obtain the blood components of LWDHP, its clinical and preclinical mechanism research progress in the treatment of senile dementia. Based on the network pharmacology of the key pathophysiological process of Alzheimer’s disease (AD), we screened the anti-AD target of LWDHP and its blood components. Results The therapeutic effect of LWDHP on senile dementia is accurate, with few adverse reactions. Its mechanism includes regulation of cholinergic system, autophagy, cerebral microvascular function, neuron apoptosis, insulin signal transduction pathway, etc. In this review, 35 blood components of LWDHP based on HPLC were collected, and their drug toxicity and safety were evaluated. The network pharmacology analysis based on the pathophysiological process of AD shows that the key components of LWDHP in the treatment of AD are Alisol A monoacetate, Linoleic acid, Alisol F, Tumulosic acid, Methyl eugenol, Palmitic acid and Pachymic acid. Conclusion This article summarizes 35 blood components of LWDHP, summarizes the synergistic mechanism of LWDHP in the treatment of senile dementia, uses network pharmacology to provide a series of potential lead compounds for the development of senile dementia’s drugs, and provides a theoretical basis for further expanding the clinical application of LWDHP.

Taking the Enterprise Resource Planning system of a loader enterprise as an example, this paper expounds on the principle of master material data coding, the existing problems in the standardization process of master material data and the measures taken.

Fire flooding, also known as in-situ combustion technology, is a mining technology that can greatly improve the recovery of heavy oil reservoir. The composition of the output of the fire flooding oil well is very different from that of other heavy oil thermal recovery wells, and shows regular changes with different stages of fire flooding. These changes have a great impact on the efficient lifting of the fire flooding oil well. Numerical simulation can be used to simulate the combustion process of fire flooding and the heat and mass transfer process in the reservoir, so as to simulate the changes of the components of the output with different stages of fire flooding, and provide guidance for the design of fire flooding lifting. The results show that it is feasible to use reservoir numerical simulation software to simulate the production performance and the change of production composition of in-situ combustion oil wells.

Flood disasters have become one of the most threatening natural disasters in the world, in which waterlogging is the most common form in the context of highly urbanized megacities. The formation of flood disaster is related to many factors and involves information from multiple sources, making it difficult be predicted. This paper integrates multi-source information data, classifies the study area into different categories according to hydrological analysis results, and combines hydrodynamic theory and ArcGIS to get the quantitative prediction of the range and depth of waterlogging under different rainfall inputs. The evaluation results provide the government with accurate and timely information of waterlogging risks and locations in order to improve promptness of emergency management such as evacuation and managing traffics.

Trans 3, 4 ′, 5-3 hydroxy 2 styrene (resveratrol) is a kind of naturally occurring polyphenols phytoalexin. Resveratrol has significant anti-cancer activity, mainly exists in grapes, berries, and peanuts, has anti-aging, protect the heart, antioxidant, antiproliferation, promote apoptosis and immune regulation. Resveratrol has been widely concerned in the treatment of cancer and autoimmune diseases resveratrol. Resveratrol synthase (RS) is a key enzyme in the synthesis of resveratrol synthase. In this study, RS containing genes were placed under the control of fruit-specific promoter RJ39 to transform tomatoes by transgenic method. The extraction of fruits containing RS genes showed an obvious absorption peak on the HPLC chromatographic map, and it also had an obvious inhibitory effect on the growth of Hela cells.

A series of xCe-Fe/ZSM-5 (x = 0, 0.25, 0.5 wt%) samples were prepared by the impregnation method, and the catalytic activity was evaluated by the selective catalytic reduction of NOx with ammonia (NH3-SCR). The physicochemical properties of prepared samples were characterized by various techniques such as X-ray diffraction (XRD), Brunner-Emmet-Teller (BET) measurement, hydrogen temperatureprogrammed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), ammonia temperatureprogrammed desorption (NH3-TPD) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). XRD and BET results demonstrated that Ce and Fe species were uniform dispersed on the surface of the ZSM-5 zeolite and the micropore structure of ZSM-5 was still maintained. H2-TPR analysis indicated that the doping of Ce created more isolated Ce4+ and Fe3+ on the surface of catalysts, and the abundant Ce4+ and Fe3+ could enhance the reduction ability of catalysts. XPS analysis suggested that the doping of Ce could generate more oxygen vacancies, thereby increasing the number of chemisorption oxygen. According to the in-situ DRIFTS and NH3-TPD results, Ce species provided more acidic sites, which is beneficial to the NH3 adsorption ability of ZSM-5 zeolite. Additionally, the abundant chemisorption oxygen, medium and strong Brønsted acid sites, excellent NH3 adsorption ability and outstanding reduction property are beneficial to the NH3-SCR reaction. Among all prepared samples, the 0.25Ce-Fe/ZSM-5 sample possessed the widest reaction temperature window and the best catalytic performance (NO conversion over 98% at 350-450 °C), which was associated with the abundant acid sites and remarkable adsorption ability of NH3, outstanding redox ability and abundant chemisorption oxygen after the doping of Ce.

The content of volatile organic compounds (VOCs) in the atmosphere will endanger the health and safety of human beings which makes it very important to develop a simple and rapid method for the determination of gas pollutants. Based on this, a new type of gas sensor was proposed for the detection of trichloroethylene in air. PEG200/ZnO nanocomposite were prepared by hydrothermal method. The materials were characterized by scanning electron microscope, X-ray energy spectrum and fourier infrared spectrum. The high selectivity of the materials was verified by using the cataluminescence (CTL) intensity of 9 kinds of VOCs on the surface of the materials as a reference. The results show that trichloroethylene can produce CTL response on the surface of PEG200/ZnO nanocomposite. Temperature, air flow rate and detector concentration all have certain effects on the CTL intensity. By comparing the CTL intensity under different reaction conditions, it is found that the suitable temperature and air flow rate are 120 °C, 180 mL/min and there is a good linear relationship between the relative CTL intensity and the concentration of the detected substance (y = 28.588 x - 285.56, R=0.9593). The gas sensor has the advantage of rapid response, and trichloroethylene can produce the maximum CTL on the surface of the material within 3 ~ 5 s.

Safety valve is an important guarantee for nuclear power plant system. Its working environment is harsh, and medium is high-temperature corrosive. It is important to study the dynamic characteristics of nuclear safety valve under unsteady condition to improve the stability and safety of nuclear power plant piping system. Using the finite element method, mass simplification and Rayleigh method, the frequency response analysis of the safety valve and the spring is predicted to predict the seismic capacity under the earthquake load. Based on the verification of the dynamic characteristics of the valve body, the stress and strain analysis of the spring is carried out. To explore the failure condition of the safety valve spring, the lateral deviation linearity of the spring was tested and analyzed by setting up the offset test bench. The results show that the safety valve with the above analysis method can meet the working requirements under the shaking condition. The research results provide an important theoretical basis for the design and analysis of nuclear safety valves.

Boiler drum water level control system is hard to develop practical mathematical model and has nonlinear, stable and delay characteristics. The traditional boiler drum water level control often uses three impulse PID control method. The existing problem of ordinary PID control strategy is: once good parameter setting, it is hard to adapt to the change of the operation of the system dynamic greatly. In order to solve the problems of the above, the research object of the subject is a certain 120 t/h boiler steam capacity, the boiler drum water level control system is designed, and the control strategies are studied. In order to obtain better contrast, the ordinary PID controller and Fuzzy controller are designed, and the control strategies of the simulation are analyzed.

The key equipment of thermal power plants such as feed pump, condensate pump, circulating pump and induced draft fan, blower fan, oxidation fan, air preheater’s vibration information are monitored and tracked. Bearing failure accounted for the largest proportion. Problems such as misalignment and unbalance are still very common. Attention should be paid to the fault diagnosis and maintenance work.

Unified power flow controller (UPFC) combines the advantages of FACTS devices of series and parallel, which is an important direction for the development of intelligent substations in the future. However, a large number of MMC submodules have become potential fault points of UPFC system. The rapid judgment of fault state and accurate positioning of fault sub-modules are the primary conditions to ensure the safe and stable operation of UPFC system, which can effectively reduce the mobile operation and maintenance time of power engineering operation and maintenance personnel, and guarantee the safety of operation and maintenance. Therefore, this paper proposes a fault diagnosis technology of intelligent substation UPFC system based on abnormal sub-module port voltage (SPVE). Experimental results show that the SPVE method has advantages in identification accuracy and rapidity.

This study investigated the hydrogeochemical characteristics of fluoride in the groundwater of Shuangliao City. This paper analyzes the effects of different forms of hydrochemistry and the chemical speciation of fluorine in water. The results showed that an area of high fluorine was located in the northern section of Shuangliao City, and the soil salinization degree was also high in this area. The chemical composition of groundwater was mainly formed by the evaporation-concentration process; both pH (weak alkaline environment) and total dissolved solids (TDS) had a positive effect on fluorine enrichment within a certain range; Na+ and F- had significant positive correlation, HCO3- and F- had a weak positive correlation, and Ca2+ was the only ion with a negative correlation with F-.

Tidal harmonic constants are necessary data for the evaluation of tidal model, tidal prediction and chart datum. Compared with the wavelet multi-scale analysis model, a new method is put forward to detect and locate tidal discrete and continuous gross error. Based on the properties of the wavelets, the wavelet suitable for detecting the gross error of tidal is selected. And taking db6 wavelet as an example, the feasibility and effectiveness of this method are proved by experiments. The results show that the method can not only simultaneously detect and locate discrete gross error and continuous gross based on high frequency information, and can detect and locate the systematic deviation caused by the zero drift according to the low frequency information. Experimental result shows that the method is more simple, the efficiency and accuracy of detecting and locating gross error are improved.

In the environmental event of hazardous release into river, quick and accurate identification of the contamination source is important for emergence response. Generally, given a noisy and finite set of monitoring information, determining the source items (i.e. location, strength and release time) is an ill-posed inverse problem. In this study, a Markov chain Monte Carlo method combined with advection-dispersion equation (ADE) was proposed for the source identification of contamination event in river system based on a Bayesian probabilistic inferential framework. Case study with analytical solution for one-dimensional ADE showed that the proposed methodology was effective and the mean posterior errors for all source parameters were lower than 3%. Case simulation based on two-dimensional ADE with numerical solution obtained similar results and further demonstrated the utility of the proposed approach for source identification. We hope the study will provide a helpful guidance to develop approach for contamination event source identification to support environmental risk management of river system.