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During the 14th Five-Year Plan period, Shanghai's five new cities (Jiading, Qingpu, Songjiang, Fengxian, and Nanhui) are designated as key development areas, with the goal of becoming future cities that lead high-quality living standards and the most ecologically advanced urban areas. In response to the evolving demands for the development of green ecological urban areas in Shanghai, the standards for urban evaluation have been revised. To fully implement the planning and construction requirements of green ecological urban areas in the new cities, a targeted green ecological planning study was conducted at the overall level for these five new cities. Following the approach of “separate cities, separate regions, and distinct focuses,” target units for green ecological urban areas were defined, and a tailored indicator system (“one city, one policy”) along with a list of key regional projects was developed.

The “14th Five-Year Plan” represents a critical window for the green and low-carbon transition. Jiading New City, characterized by its pioneering role as a “Low-Carbon Urban Area Leader,” focuses on advancing the development of a green ecological urban district and explores the construction of a livable, green, and low-carbon new city. This paper takes the Yuanxiang Lake Central Activity Zone as the subject, elaborating on the green ecological positioning, green ecological indicator system, planning strategies, and the implementation safeguard system. It innovatively proposes the planning and design scheme of a “Green Gene Chain” to activate the Yuanxiang Lake Central Activity Zone, establishing it as a model for the green ecological urban district of Jiading New City and providing a reference for the green ecological planning and construction of other new citys.

The 20th Party Congress report proposed to improve the grid-based management, refinement of services, information technology to support the grassroots governance platform, and improve the urban and rural community governance system [1, p. 24]. Grass-roots social governance is the basis of the entire national governance system, which concerns the vital interests of millions of people. At present, the government concentrates funds and material resources on infrastructure construction, and while the hardware environment at the grassroots level is improving, the construction of soft power is seriously lagging behind, and residents’ awareness of participation and public spirit are seriously lacking, so grassroots governance needs to be transformed. The basic function of social credit system is to form incentives and constraints for various subjects with the help of credit evaluation mechanism, so as to realize effective social governance. The establishment of social credit system can not only create an environment to serve social governance, but also provide important support for the modernization of social governance system and national governance capacity. Thus, under the strategic choice of building a comprehensive social credit system, combining an effective social credit system with grassroots social governance is an inevitable choice for China’s future development. Meanwhile, along with the accelerated development of digitization in China, the digitization of social credit system construction has become a powerful boost to promote credit governance. The digital transformation of social credit system can fully activate the path of credit information formation and collection in the traditional social credit system, optimize the operation mechanism and application scenario of credit evaluation mechanism, and thus maximize the functional utility of credit-enabled grassroots social governance. Based on this, this paper attempts to take the many challenges faced by grassroots governance as a logical starting point, take the “moral bank” in Yuyao, Zhejiang Province as a case study, trace how the construction of social credit system empowers grassroots social governance in the context of digitalization, explore the operation mechanism and practical effects of it, and extract corresponding insights.

Nitrogen-doped porous carbons with BET surface area of 1068.2–3314.5 m2/g and nitrogen contents of 3.2–6.5% were prepared with solid waste grape-seed as raw material, NaNH2 as activator and nitrogen source at low activation temperature. Super The activation mechanism of NaNH2 on hydrothermal carbon precursors was first explored by thermodynamic analysis and TG-IR, which provided theoretical support for pore forming of carbon materials. Maximum CO2 and CH4 adsorption capacity at 273 K and pressure of 101 kPa was 5.42 and 1.76 mmol g−1 respectively, which are higher than those of majority of carbon derived from most solid wastes reported in literature. IAST selectivities of GS-3-450 with the largest BET surface area for CO2/CH4 (40v/60v), CO2/N2 (15v/85v), CH4/N2 (50v/50v) were found to be 20.3, 71.4, 6.0 under 101 kPa and 298 K respectively. The competitive adsorption of GS-3-450 for CO2/CH4 (40v/60v), CO2/N2 (15v/85v), CH4/N2 (50v/50v) gases mixture were examined through breakthrough experiments, and the results showed that the breakthrough time of CO2 was longer than that of CH4 and N2, which was beneficial to the separation of CO2 from gases mixture. Eight cycles of CH4 adsorption–desorption studies revealed that the material exhibited excellent recycling stability. Low temperature preparation method, excellent BET specific surface area and total pore volume, as well as excellent adsorption ability of CO2 and CH4 make it have a very great potential for the capture of CO2 and CH4. [ABSTRACT FROM AUTHOR]

Although carbon material are widely used for gas separation and adsorption due to its well-developed pore structure, their prevalent wide pore size distribution and scarcity of active adsorption sites limit its gas adsorption capacity. Therefore, in this paper, a series of N-doped microporous carbon adsorbent materials were prepared via utilizing cheap starch as the carbon source and the synthesized melamine resin as the N-doped modifier with the assistance of hydrothermal conversion and high temperature activation by KOH.BET test showed that MF@Cs was a typical microporous carbon material with a pore size distribution of 0.3–2 nm, and its most accessible pore size was about 0.6 nm,which benefits the adsorption of CO2 and CH4. MF@C–1–750 porous carbon material present prominent pore structure parameters, with a maximum specific surface area of 2415.9 cm2/g, a total pore volume of 1.36 cm2/g, and a maximum ultramicro pore volume of 0.42 cm2/g at 0.3 ~ 1.0 nm. MF@Cs porous carbon materials show high static adsorption capacity for CO2 and CH4, the adsorption capacity of CO2 of MF@C–1–750 is as high as 6.54 mmol/g at 273 K and 100 kPa, which is attributed to the excellent ultramicro pore volume of carbon materials. MF@Cs porous carbon material is expected to play a huge application potential in the separation and enrichment of CO2 in the future, due to its simple preparation and low cost, excellent specific surface area, outstanding ultrafine pore capacity and high adsorption capacity of CO2 gas. [ABSTRACT FROM AUTHOR]

Reasonable design of adsorbents for separating and purifying CH4 in coalbed methane is important to achieve sustainable development. However, KOH activation, the most widely used method for preparing activated-carbon adsorbents, requires the addition of a high proportion of KOH, which has disadvantages such as high cost and corrosion. In this study, a low proportion of KOH/KMnO4 is used as an activator and a mechanical ball-milling method is used to prepare cellulose-based microporous carbon for the selective adsorption of CH4 in low-concentration coalbed methane. The prepared microporous carbon has a large ultramicropore volume and narrow pore size distribution. The Vmic (<1 nm) of ACQ60 is 0.39 cm3/g, and the most probable pore size is 0.42 nm. At 273 K and 101.3 kPa, the CH4 adsorption capacity of this sample is up to 3.22 mmol/g. Ideal adsorption solution theory simulations show that CH4/N2 selectivity is 7.82. The ACQ60 regeneration adsorption performance was evaluated via a dynamic penetration experiment. After six cycles, the CH4 penetration time difference was found to be minor. This study serves as a reference for the excellent performance of carbon materials with rich narrow microporous structures applied to the effective separation of CH4 in low-concentration coalbed methane. [ABSTRACT FROM AUTHOR]