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This paper aims to study the direct synthesis of imino methyl ether amino resin using commercially available formaldehyde, melamine and methanol through one-step two-stage catalysis.

Initially, melamine undergoes a reaction with formaldehyde to form hydroxylmethylation melamine in a basic setting. Subsequently, hydrochloric acid is incorporated to facilitate the etherification process. The study delves into the impact of various factors during the etherification phase, including the quantity of methanol, the temperature at which etherification occurs, the number of etherification cycles and the amount of catalyst used, on the synthesis of imino methyl-etherified amino resins. Ultimately, the most favorable conditions for etherification are identified through comparative analysis to evaluate the resulting synthesized products.

The methyl-etherified amino resin, characterized by a stable structure and consistent performance, was efficiently synthesized through a one-step, two-stage catalytic process. Optimal conditions for the etherification stage were determined to be a reaction temperature of 35°C, a melamine to methanol ratio of 1:24 and an addition of hydrochloric acid ranging from 2.2 mL to 2.5 mL. Remarkably, the resulting resin notably enhanced the water resistance, salt resistance and gloss of the canned iron printing varnish coatings.

Amino resins, known for their broad applications across numerous industries, face sustainability and operational efficiency hurdles when produced through traditional methods, which predominantly involve the use of a 37% formaldehyde solution. To tackle these issues, our research introduces an innovative method that add 37% formaldehyde to facilitate industrial production. The use of 37% liquid formaldehyde in this paper has two benefits: first, it is convenient for industrial application and production; Second, it is convenient to provide mild reaction conditions at lower concentrations because the amino group is relatively active, which is convenient for the preservation of the amino group and integrates it with a one-step, two-stage catalytic process. The primary objective of our study is threefold: to reduce the environmental footprint of amino resin synthesis, to optimize the use of resources and to improve the economic viability for its large-scale production. By employing this new strategy, we try to provide a more sustainable and efficient manufacturing process for amino resins.

In this study, solid formaldehyde, benzoguanamine and butanol were used to synthesize butylated benzo-amino resin by one-step-two-stage method.

This research first examined the influence of solid formaldehyde content on the hydroxymethylation phase. Subsequently, the effects of butanol content, etherification time and hydrochloric acid content on the formation of benzo-amino resin during the etherification stage were studied in detail. In addition, the reaction process was further analyzed through interval sampling withdrawing during the hydroxymethylation and etherification stages. Finally, the synthesized benzo-amino resins were used in the production of high solid content polyester and acrylic coatings and the properties of that were also evaluated.

Based on the experimental findings, the authors have successfully determined the optimal process conditions for the one-step-two-stage method in this study. The hydroxymethylation stage demonstrated the most favorable outcomes at a reaction temperature of 60°C and a pH of 8.5. Similarly, for the etherification stage, the optimal conditions were achieved at a temperature of 45°C and a pH of 4.5. Furthermore, the investigation revealed that a ratio of benzoguanamine to solid formaldehyde to n-butanol, specifically at 1:5.2:15, produced the best results. The performance of the resulting etherified benzo-amino resin was thoroughly evaluated in high solid content coatings, and it exhibited promising characteristics. Notably, there was a significant enhancement in the water resistance, solvent resistance and glossiness of canned iron printing varnish coatings.

Amino resin, a versatile chemical compound widely used in various industries, presents challenges in terms of sustainability and operational efficiency when synthesized using conventional methods, primarily relying on a 37% formaldehyde solution. To address these challenges, the authors propose a novel approach in this study that combines the advantages of the solid formaldehyde with a two-stage catalytic one-step synthesis process. The primary objective of this research is to minimize the environmental impact associated with amino resin synthesis, optimize resource utilization and enhance the economic feasibility for its industrial implementation. By adopting this alternative approach, the authors aim to contribute toward a more sustainable and efficient production of amino resin.

The purpose of this paper is to study the impact of government supervision and market environment on farmers' pesticide application behavior, as well as the intermediary effect of farmers' literacy, and investigate the substitution effect between government supervision and market environment.

In this paper, logit and Poisson regression models were used to investigate the comprehensive impact of government supervision and market environment on farmers' pesticide application behavior, and the intermediary effect model is used to examine the intermediary effect of farmers' literacy.

Government supervision is an important constraint for the formation of individual behavior paradigm, but it has both positive and negative effects, depending on different instruments. The market subject constraint and market incentive are two important ways that the market environment affects Chinese farmers' pesticide application behavior. Farmers' literacy plays a partial mediating role in the influencing mechanism of government and market factors. The government supervision and market environment, two different constraint forces, have substitution effects in the process of regulating farmers' pesticide application behavior.

In the influence mechanism, farmers' literacy, such as values, responsibilities and skill requirement related to scientific pesticide use, was included into the analysis framework as intermediary variables. The authors found that government supervision and market environment not only directly affect farmers' pesticide application behavior but also indirectly affect farmers' pesticide application behavior through farmers' literacy.

This paper analyzes the factors that potentially affect grain security in China and reviews the techniques used for prediction. It reviews and compares forecasts for grain security in 2020 and 2030 with the aim of making some judgments, from the perspective of grain supply and demand, about the future grain security situation in China.

In this article, the paper will introduce the methods and results of the forecast and also focus on the predictions for grain security in 2020 and 2030 in order to give a clear review of previous researches in this regard.

The results indicate that the traditional threats to food supply and demand in China still exist, while demand for biomass energy continues to rise. With regard to grain aggregate, the grain supply-demand balance will still be relatively tight for both 2020 and 2030. In terms of structure, grain for feed will experience increase – mainly driven by the supply of corn – adding to the unabated structural issues confronting regional grain supply and demand. In the future, therefore, China should try to preserve favorable factors that increase grain production, optimize grain structure and production, maintain the proper scale and make-up of grain imports and exports, and work for a sound global trading environment for grain.

This article contributes to existing literature by analyzing the factors affecting grain security in China and reviewing prediction techniques and forecasts for grain security in China in 2020 and 2030. The findings suggest that China needs to take appropriate measures to ensure future grain security.

The purpose of this paper is to test the impact of the soybean rejuvenation plan and the subsidy on farmers' land allocation decisions, which may reference policy adjustment from a micro perspective.

The paper develops a multi-objective optimized programming model on farm-level, which simulated the land-use changes, as well as the resulting changes in benefits of the rational “typical farm”. The simulation scenarios include changes in subsidy policy and production efficiency, and the baseline scenario was the production status in 2018.

The results show that an increase in soybean producer subsidy will encourage farmers to allocate more land for soybean planting, which can be considered as a policy tool in promoting soybean production in China. Besides, the effect of subsidy in adjusting soybean acreage for farms is further affected by external conditions such as production technology (such as breeding technology, pesticide and fertilizer application efficiency). Meanwhile, large-scale farms show more significant land adjustments when facing changes in policies and external conditions.

The value of this paper is to simulate the effects of soybean policy and subsidy change on farmers' land-allocation decisions through a multi-objective farmer decision-making model, which provides a micro perspective to understand the implementation effect of the soybean revitalization plan.

Some researchers argue that consumers’ lack of knowledge is an important factor increasing risk for a new product derived from emerging agricultural technology. The purpose of this paper is to discuss the potential impacts and the differential effects of subjective and objective perceptions on Chinese consumers’ preferences for the application of a novel biotechnology.

Taking transgenic technology as an example and employing data from a survey of 1,000 consumers in Jiangsu Province, the authors develop a mixed-process regression model based on Fishbein’s multiple attributes attitude model.

The results suggest that there are apparent differences between Chinese consumers’ subjective perceptions and objective perceptions concerning transgenic technology and genetically modified (GM) food, and there exists certain selective perceptions of the emerging biotechnology. Having a subjective perception concerning transgenic technology has a positive effect on consumers’ overall attitudes, whereas subjective and objective perceptions concerning GM foods have a negative effect on consumers’ overall attitudes. Self-identification generated from subjective perception occupies a dominant position in determining consumers’ attitudes.

Consumers’ attitudes regarding an agricultural product depend on their perception of the attributes of the technology used to produce such a product. This study attempts to distinguish and empirically test urban consumers’ subjective perceptions (self-assessed or perceived) and objective perceptions (obtained from a test) about transgenic technology and GM foods and the impact of these four types of perception on the consumers’ attitudes regarding the application of transgenic technology. In this paper, the authors construct a mixed-process regression model to address the possible endogeneity of the perception variables.

The purpose of this paper is to develop a novel integrated risk assessment method from the system perspective to evaluate the risk of the cross-regional mega construction project (CMCP). Furthermore, this paper aims to confirm the core risk source factors and refine the risk management strategies of CMCPs through a case study.

Based on the analysis of the risk system of CMCPs, the concept model and risk assessment principles of integrated risk assessment were confirmed. The risk source factors and project objectives of the CMCP were identified from a literature review, export interview and case analysis. According to the vulnerability theory, the integrated risk assessment model was developed by involving vulnerabilities, threats, objectives and interaction of those factors synthetically. Then, ZW high-speed railway from China was analyzed to verify the feasibility and effectiveness of the proposed method.

As a result, 12 threat factors and 12 vulnerability factors were identified. Based on the case study, the main external threat comes from T13 (conflicts of interest between local governments) and T23 (harsh natural environment); the most easily exploited internal vulnerabilities were V11 (complexity of technology), V13 (lack of experience in technical application), V21 (inadequate experience) and V23 (lack of interest coordination mechanism). Moreover, the economic objective was most affected.

It is essential to develop an interest coordination mechanism for CMCPs. The harsh natural environment is a critical factor, but it also promotes technological innovation and iteration. Public opinions in different regions are critical for CMCPs, and more emphasis should be placed on public opinion surveys of CMCPs. Moreover, diverse and flexible environmental protection strategies should apply in CMCPs.

This research has the following three contributions. First, based on vulnerability theory, an integrated risk assessment approach of CMCPs is developed, which enriches the risk measurement method system and provides inspiration for future research on risk in the construction industry. Second, the risk sources of CMCPs are identified from the perspective of vulnerability and threat to provide clear guidance for the risk management of CMCPs. Third, the core risk source factors and management strategies confirmed by the case study will be beneficial for various governments in different regions and project managers to optimize the project management scheme, as they are transferable management experiences.

Extant research shows mixed results on the impact of expressed negative emotions on donations in online charitable crowdfunding. This study solves the puzzle by examining how different types of negative emotions (i.e. sadness, anxiety and fear) expressed in crowdfunding project descriptions affect donations.

Data on 15,653 projects across four categories (medical assistance, education assistance, disaster assistance and poverty assistance) from September 2013 to May 2019 come from a leading online crowdfunding platform in China. Text analysis and regression models serve to test the hypotheses.

In the medical assistance category, the expression of sadness has an inverted U-shaped effect on donations, while the expression of anxiety has a negative effect. An appropriate number of sadness words is helpful but should not exceed five times. In the education assistance and disaster assistance categories, the expression of sadness has a positive effect on donations, but disclosure of anxiety and fear has no influence on donations. Expressions of sadness, anxiety and fear have no impact on donations in the poverty assistance category.

This work has important implications for fundraisers on how to regulate the fundraisers' expressions of negative emotions in a project's description to attract donations. These insights are also relevant for online crowdfunding platforms.

Online crowdfunding research often studies negative emotions as a whole and does not differentiate project types. The current work contributes by empirically testing the impact of three types of negative emotions on donations across four major online crowdfunding categories.

Using survey data from Shandong, Henan and Guizhou provinces of China, the purpose of this paper is to accurately measure the impact of rural residents’ financial education on financial literacy.

This paper chooses one province from the Eastern, Central and Western Regions of China, namely, Shandong, Henan and Guizhou, respectively, and 1,565 samples are obtained through a questionnaire survey. First, the paper constructs a financial literacy assessment framework and, then, scores the financial literacy of the respondents. Second, using ordinary least squares, feasible generalized least squares method and forward search method, the paper estimates the impact factors of financial literacy level. To avoid sample selection errors and endogeneity problems, the authors divide the respondents into treatment group (participated in financial education) and control group (non-participating in financial education) and, then, adopt propensity score matching (PSM) to analyze the impact of rural residents’ financial education on financial literacy.

The results show that education level and risk level have significant impact on rural residents’ participation in financial education, and some unobservable abilities and qualities also affect their participation. Therefore, the process of rural residents’ participation in financial education exists, which gives rise to self-selection and endogeneity problems; financial education is promoting rural residents’ financial literacy, but the effect of promotion becomes smaller after taking into account sample self-selection and endogenous problems. Rural residents of female, higher age, single, higher education level, higher parental education level, agricultural type, higher family annual per capita income and lower risk level show stronger effects on their financial literacy level, if they participate in financial education.

The survey sample was drawn from three provinces randomly but the site selection was not random. The implication is in rural China, financial education has positive effect on residents’ financial literacy level but considering the sample self- selection and endogenous nature, its impact becomes smaller.

The government should encourage rural residents to participate fully in financial education activities, especially those with a low educational level, low risk preference and mainly engaged in agricultural production.

The effect of financial education on financial literacy has not reached a consistent conclusion, and there is fewer quantitative discussion about this issue. The originality of this paper is based on the Organization for Economic Co-operation and Development evaluation index system; this paper constructs the evaluation index system of rural residents’ financial literacy in China and uses the PSM method to accurately measure the effect of financial education on financial literacy.