Green innovations for sustainable development of China: Analysis based on the nested spatial panel models

Improving green innovation efficiency (GIE) is crucial for attaining sustainability in China's stage of high-quality development. However, there is a paucity of research on the roles of and links among the government and market in GIE. This study bridges this research gap by unifying marketization, local government competition, and GIE into one empirical framework. First, we extend a super-efficiency Ray slacks-based measure model to evaluate provincial GIE in China during 1997–2018 and then analyze its evolution of spatial-temporal dynamics. Subsequently, marketization, local government competition, and GIE are incorporated into a nest of spatial panel models to address the endogeneity concerns resulting from model misspecification and omitted variables. The empirical results show that China's GIE at the national level is only 0.4813, and above 80% of provinces are far from reaching the green innovation frontier. Moreover, the observed imbalance in GIE between regions continues to worsen; notably, this coincides with the emergence of a pattern under which the gap between the north and south is widening. Furthermore, the seven spatial panel models assessed in this study reveal that local government competition not only has a direct inhibitory effect on GIE, but also indirectly impedes the corresponding promotional effect of marketization. This finding provides new evidence supporting the “grabbing hand of government” view and sheds light on the behaviors of the market and government in green innovation development.     

Comparison of liquefaction behavior of granular material under SH- and Love-wave strain conditions by 3D DEM

In the study of liquefaction behavior associated with seismic loading conditions, it is often assumed that liquefaction occurs owing to the upward propagation of shear waves, despite evidence that liquefaction damage may result from or be aggravated by horizontally propagating surface waves. In this study, a series of numerical tests, based on the three-dimensional discrete element method, is performed to examine the liquefaction behavior of granular materials under Love-wave strain conditions. The response of granular packings under horizontally polarized shear- (SH-) and Love-wave strain conditions is discussed at both macro- and microscales. The simulation results indicate that, at the macroscale, the effective stress reduction ratio increases more rapidly under Love-wave strain conditions than under SH-wave strain conditions. Based on the concept of energy, the granular materials under Love-wave strain conditions can be considered more vulnerable to liquefaction than those under SH-wave strain conditions. Microscale analysis indicates the spatial rotation of the dominant direction of backbone force-chains under Love-wave strain conditions. In addition, focus here is placed on the coordination number, which represents the average contact number per particle. The difference in the degradation speed of the skeleton structure of the granular packings between the SH- and Love-wave strain conditions may not appear until the coordination number has decreased to a critical value of around 4. After the coordination number has approached approximately 3, the granular packings become unstable and soon liquefy. The minimum mean effective stress is discussed herein.     

Ni–P alloy@carbon nanotubes immobilized on the framework of Ni foam as a 3D hierarchical porous self-supporting electrode for hydrogen evolution reaction

The development of self-supporting electrodes that exhibited both high efficiency and good durability remained a challenge in the field of hydrogen energy utilisation. Here, we designed a self-supporting 3D hierarchical porous electrode by filling carbon nanotubes (CNTs) loaded with Ni–P alloy into the framework of nickel foam (NF). Firstly, CNTs were decorated with a catalytically active Ni–P alloy via electroless plating (Ni–P@CNTs). Then, the Ni–P@CNTs were filled and anchored onto the framework of NF via electroplating to synthesise a self-supporting electrode (Ni–P@CNTs/NF). The Ni–P@CNTs/NF exhibited an excellent catalytic performance toward the hydrogen evolution reaction (HER) in 1 M KOH electrolyte, with an overpotential of 53 mV at 10 mA cm^?2, a small Tafel slope of 101.56 mV dec^?1 and excellent long-term durability. This facile and effective strategy might provide a new path to the design of self-supporting electrodes with enhanced HER catalytic.     

Cobalt-based coordination polymer-derived hexagonal porous cobalt oxide nanoplate as an enhanced catalyst for hydrogen generation from hydrolysis of borohydride

As cobalt is an effective metal for catalyzing hydrolysis of NaBH₄ to produce H₂, Co₃O₄ is a proven catalyst for facilitating NaBH₄ hydrolysis. Since Co₃O₄ can be designed into various morphologies, 2-dimensional plate-like Co₃O₄ can offer large contact surfaces. If the planar surfaces can be even porous, forming porous Co₃O₄ nanoplate (PCNP), this PCNP would be a promising catalyst for HG. Therefore, in this study, a facile approach is developed to fabricate such a PCNP for H₂ generation (HG) from NaBH₄ hydrolysis. Specifically, a cobaltic hexagonal nanoplate-like coordination polymer, which is synthesized via coordinating Co²⁺ with thiocyanuric acid (TA), is adopted as a precursor. Through calcination, Co-TA (CTA) is transformed into hexagonal nanoplate-like Co₃O₄ with pores to become PCNP. More importantly, PCNP showed quite different surficial reactivity and textural properties from commercial Co₃O₄ nanoparticle (Co₃O₄ NP), enabling PCNP to possess a much more superior catalytic activity towards HG from NaBH₄ hydrolysis. PCNP also showed a comparatively low E_a of 35.12 kJ/mol in comparison with the reported catalysts, even precious metal catalysts, and it could be reused up to 10 cycles for HG with stable catalytic activities. These features confirm that PCNP is an advantageous catalyst for HG from NaBH₄ hydrolysis.     

国土空间规划体系中 景观设计学科与行业的困惑及机遇

A true understanding of Ecological Civilization Construction is key to comprehend the connotation and goals of China’s territorial spatial planning, which echoes the ideological keynote of the country’s upgrade of socio-economic development mode. Missioned as a means to public policy making, territorial spatial planning develops roadmaps for Ecological Civilization Construction by addressing macro spatial governance problems such as the shortage of resources, severe environmental pollution, and ecosystem degradation. Furthermore, the author interprets the relationship between ecological restoration and territorial spatial planning system, and argues that the territorial spatial planning system should employ a macro-medium-micro hierarchy in scale while focusing on life-circle ecological restoration planning and implementation. In addition to the necessity of developing crossadministrative border plans, the author emphasizes the importance of multi-disciplinary cooperation. Then, he points out that "The Two Assessment Standards" should value regional characteristics and avoid to indiscriminately apply planning and design patterns in different cases. Finally, the author puts forward suggestions to practitioners in Landscape Architecture and other allied professions to prepare themselves by selfretraining with new concepts, methodologies, and technologies to be more competent for the contemporary needs of territorial spatial planning.     

主编寄语

Through his recent visits to three cities facing severe and challenging living environment, the author had a deeper insight into the symbiosis between human and nature. In Mexico City, the capital of Mexico, urban construction practices against floods and for water supply encroach on natural ecological infrastructure, resulting in the exhaustion of local water resource, city sinking, and erased indigenous cultural landscape of floating gardens. In Dhaka, the capital of Bangladesh, where water bodies are heavily polluted, scarce urban parks become the only refuge for citizens. Finally in Bangkok, the capital of Thailand, estuary gates built to block floods invade the once prosperous canals, accelerating the decline of floating communities and markets and exacerbating traffic congestion and air pollution. Learning from these cases, cities must become better at territorial spatial planning and have the foresight to develop and grow while preserving and improving existing ecosystems. Essentially, territorial spatial planning and ecological restoration is to work with and by nature that would provide generous ecosystem services for humans, and, eventually, to increase people’s well-being and enhance cities’ development of sustainability.     

Delineation of spring capture zones in southern Great Basin,USA based on modeling results and geochemical data

The protection zones or capture zones of springs in desert environments can be hard to identify, but they are critical to spring protection. Most springs fed by regional aquifers are susceptible to contamination and groundwater development. The U.S. Environmental Protection Agency has established hydrogeologic mapping methods to delineate protection zones for springs. However, it is often difficult to determine a regional aquifer system's flow pattern with this technique alone, and the use of these methods is not conducive to efficient groundwater management. Particle tracking analysis using a well-conceptualized and calibrated numerical model for the three-dimensional groundwater flow domain feeding a given group of springs can help facilitate the identification of spring capture zone boundaries. Building upon this basis, a multifaceted approach was developed to define clear boundaries of the capture zones for the springs in the Furnace Creek, Ash Meadows, and the Muddy River areas in the southern Great Basin, USA. Capture zones were first delineated from inverse particle tracking and Hydrologic Unit 12 watersheds. Afterwards, they were adjusted based on water budgets, geology, and hydrologically significant faults. Finally, a geochemical analysis of the groundwater chemistry and isotopic data was conducted to verify the extent of each spring capture zone. This multifaceted approach adds confidence to the new delineations.     

都市形式与空间经验：比较都市史与规划史阅读书目简明导言

本文针对建筑学与城乡规划学领域关注“形式”的学科或专业特点，以建筑史、社会史、文化史等几种视角梳理了20世纪下半叶以来都市史研究主题下的重要文献。借助以此揭示出的不同方法取向在都市“空间”再现中的特征及其差异，试图建议，出于应对相关学科体系“范式转移”——特别表现在给予“主体经验”更多关注——的现实需求，都市史写作或许需要调整专业分工的单一方法论，寻找更加多元化的研究路径。     

Diversity embedded rate configurable GSM and a low complexity detection method

This paper presents an energy efficient transmission method that is suitable for emerging large scale MIMO scenario, by combining space time coding and spatial multiplexing with GSM. The proposed Diversity Embedded SM (DESM) provides required Quality of Service (QoS) for a high priority data and at the same time maintains a fair transmission rate by spatial multiplexing a low priority data. Only limited feedback is required and the system can be configured for different diversity/non-diversity stream rates, as per the required QoS. Utilizing some peculiarities of the channel matrix of the system, a QR decomposition based detection method that requires only four receiving antennas is shown to have good performance. The computational complexity of detection is less compared to the existing GSM detection schemes, for reasonable number of transmit and active antennas. The effect of incorporating diversity on the rate of the system is also analyzed.