An empirical study on the green effects of new energy vehicle promotion in the context of global carbon neutrality

In the context of global carbon neutrality,new energy vehicle promotion(NEVP)has become an important means of reducing carbon emissions.This paper constructs a theoretical model and uses panel data on NEVP in 21 countries from 2012 to 2018 to empirically examine the green effect of NEVP.The results indicate the following:(1)NEVP significantly reduces greenhouse gases emissions,and the green effect can be transmitted and diffused through a direct path.(2)Replacing fuel-fired vehicles and accelerating the end-of-life vehicle scrapping process significantly conducted the green effect,and aggravating traffic congestion was not statistically significant.(3)The transmission mechanism of the green effect is regulated by regional economic heterogeneity.In regions with better development of fuel-fired vehicles,the transmission of the green effect is subject to the elimination of fuel-fired vehicles and traffic congestion governance,and the transmission efficiency is low.However,regions with a relatively weak fuel-fired automobile industry foundation show a strong“advantage of backwardness”,and the green effect is more prominent.This means that global NEVP should be further accelerated to achieve the green effect and the goal of global carbon neutrality.

Threshold effects of tourism agglomeration on the green innovation efficiency of China's tourism industry

Industrial agglomeration is an essential and effective way to integrate resources and elements. Its impact on the green innovation efficiency of the tourism industry is a process of continuous development and dynamic change. This paper, based on the provincial panel data from 2006 to 2015, uses super SBM model to measure the green innovation efficiency of China's tourism industry.The threshold regression model is employed to conduct empirical tests of the nonlinear threshold effect of agglomeration on the green innovation efficiency of tourism industry. The inter-provincial differences of various threshold effects and their possible causes are analyzed. Results indicate that the green innovation efficiency of China's tourism industry is generally growing, while regional disparity is significant with a gradient decrease along the eastern-central-western regions. There is an obvious positive nonlinear relationship between tourism agglomeration and green innovation efficiency. It is also found that with the increase of agglomeration, its influence is at a high level. As the level of agglomeration crosses the first threshold, its impact is at a low level, and when it crosses the second threshold, the impact of tourism agglomeration is at an intermediate level. Finally, this paper proposes the basic path and some policy recommendations to promote the green innovation efficiency of the tourism industry in China.

Catalytic effects of Cu-Co~* on the thermal decomposition of AN and AN/KDN based green oxidizer and propellant samples

This paper presents the catalytic effects of Cu-Co~* catalyst on the decomposition of AN and AN/KDN based oxidizer and propellant samples. Ozawa-Flynn-Wall(OFW) iso-conversional method was used for the kinetic studies and to compute the activation energy(Ea) values for various decomposition steps of the prepared oxidizer and propellant samples in the temperature range of 50 e500C. TG-DTG experiments were carried out for both oxidizer and propellant samples at the heating rates of 3, 5, and 10C/min. AN/KDN based oxidizer samples were prepared by an evaporative co-crystallization method. Citric acid sol-gel method was used for the synthesis of Cu-Co~* catalyst. The propellant sample contains HTPB as the fuel binder along with other ingredients such as TDI, DOA, and Glycerol. The Cu-Co~* catalyst was used as 2% by weight to the total weight of catalyzed oxidizer and propellant samples. It was observed from the present study that, Cu-Co~* catalyst helps in reducing the Ea values for AN and AN based propellant samples. However, with the percentage increment of KDN in the AN crystals, Ea value increases.Further, it was observed that Cu-Co~* catalyst stabilizes the initial partial decomposition of KDN.

Inhibitory Effect of Green Tea Extract on the Carcinogenesis Induced by Asbestos Plus Benzo(a)pyrene in Rat

In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observcd that the incidcnce (16.0%) of lung carcinomas was lowel, and the survival time (376 days) of the first case of carcinoma and the mean survival time (758 days) of the rats with carcinoma were higher in the group of rats drinking 2% green tea extract for life than in the positive group (without drinking green tea extract). The mortality ratio (0.5047) was smaller in the cxperimental group than in the positive control group, and the survival curve of the experimental group significantly raised up, in comparison with the positive group.

CONTEMPORARY CLIMATIC CHANGE OVER THE QINGHAI-XIZANG PLATEAU AND ITS RESPONSE TO THE GREEN-HOUSE EFFECT

The knowledge of contemporary climatic change over the Qinghai Xizang (Tibet) Plateau (QXP) has been inadequate for a long time due to lack of enough observational data. In this paper, on the basis of monthly temperature and precipitation data in 1961-1990 from 48 stations on the QXP, the temperature data are extended backward to 1901 with an empirical orthogonal function (EOF) method, microscopic characteristics of contemporary climatic change over the QXP are analyzed, and the response of the plateau climate to global warming is discussed in combination with atmospheric general circulation model (GCM) outputs. The results show that the plateau climate, as a whole, has been warming since the early part of this century, that the precipitation has generally been increasing during the recent 30 years, and that these climatic trends seem to be related to the enhanced green house effect induced by increasing CO 2 concentration in the atmosphere.

IMPROVING THE EFFECT OF GREENING ON HEAT ISLAND IN URBAN RESIDENTIAL DISTRICTS BASED ON REMOTE SENSING AND GIS ANALYSIS

Analyzing the thermal distribution on plane conditions objectively is difficult due to lack of enough meteorological observation stations within urban residential areas. In this paper satellite observations synchronous or quasi-synchronous with ground observations are adopted, and a teleconnection model is built between the satellite spectral and surface temperature for quantitative retrieval of temperature. Furthermore, by combining the satellite data with other multiple factors, a GIS comprehensive analysis model and a functional evaluation method for urban residential districts are established, which are used to study the relation between the air temperature and media characteristics on ground as well as the greening cooling effect in recent years in Shanghai. The results show that the air temperature in greened urban residential districts is generally lower than the average temperature and much less than the highest one. In general,the average air temperature in the greened area is at most 1.19℃ lower than the maximum temperature in the districts,which is 0.67℃ and 0.55℃ lower than that of the highest for buildings and roads respectively. The temperature is inversely proportional with greening fraction but is directly proportional with the ratio of roads and buildings. The higher the greening fraction in internal residential districts, the lower the temperature, and the higher the ratio of road and building is, the higher the temperature.

Measurement of Cooling Effect of Building Environment Greening

A series of measurements showed that community greening and trees shading had different degree of cooling effect. The cooling effect of wall greening was related to factors such as heat storage capacity and the orientation of the wall, climatic conditions. As compared to the heat reduced by sheltering the solar radiation, the heat absorbed by plant transpiration had greater cooling contribution. Comprehensive considering environment, technology and economics factors, the building district greening should take trees as the priority. The trees shading can significantly drop indoor temperature and temperature fluctuation, also created better condition for night-time natural ventilation.

Annealing effect on structure and green emission of ZnO nanopowder by decomposing precursors

ZnO nanopowder is successfully synthesized by annealing the precursors in oxygen gas using the chemical precipitation method. Structural and optical properties of thus synthesized ZnO nanopowder are characterized by scanning electron microscopy （SEM） and photoluminescence （PL）. The morphology of ZnO nanopowders evolves from nanorod to cobble as annealing temperature increases from 500 to 1000℃, while spiral structures are observed in the samples annealed at 900 and 1000℃. The PL spectra of ZnO nanopowder consist of largely green and yellow emission bands. The green emission from ZnO nanopowder depends strongly on the annealing temperature with a peak intensity at a temperature lower than 800℃ while the yellow emission is associated with interstitial oxygen Oi.

Effect of Green Quantum Well Number on Properties of Green GaN-Based Light-Emitting Diodes

In GaN-based green light-emitting diodes（LEDs） with different green quantum well numbers grown on Si（111）substrates by metal organic chemical vapor deposition are investigated. It is observed that V-shaped pits appear in the AFM images with the green quantum well number increasing from 5 to 9, and results in larger reverse-bias leakage current. Meanwhile, in the case of the sample with the number from 5 to 7 then to 9, the external quantum efficiency increases firstly, and then decreases. These phenomena may be related to the size of V-shaped pits in the active area and the distribution of electrons and holes in the active area caused by V-shaped pits. The optimal number of green quantum wells is determined to be 7.

COMPARATIVE STUDY ON THE INHIBITORY EFFECT OF GREEN TEA, COFFEE AND LEVAMISOLE ON THE HEPATOCARCINOGENIC ACTION OF DIETHYLNITROSAMINE

The present study aimed at clarifying whether Chinese green tea, coffee and levamisole (LMS) have similar Inhibitory effect on hepatocarclnogenesis induced by diethylnltrosamine (DEN) as they had been proved in our previous aflatoxin B1 (AFB1) experiments. Male Wistar rates were divided into control (A), green tea (B), coffee (C) and levamisole (D) groups. All rats received the same basic DEN treatment according to the program originally designed by Solt and Farber. During the two weeks before and one week after i. p. injection of DEN, the group B, C and D were given 2. 5% green tea, 5% coffee and 0. 1% LMS diet, respectively. The results demonstrated that coffee, LMS and , in particular,green tea showed Inhibitory effect against DEN-induced hepatocarcinogenesis, indicating that green tea can be used as chemopreventive agent for DEN-, as well as for AFB1-induced hepatocarcinogenesis.

Lemon Effect of Green Agricultural Products and Its Marketing Strategy

The paper introduces the lemon effect of green agricultural products,analyzes the formation reasons of the lemon effect of green agricul-tural products and summarizes problems brought by the effect,such as malicious deception and high price.The paper proposes countermeasures toavoid the lemon effect of green agricultural products from a perspective of marketing.The first is to strengthen the quality supervision of green agri-cultural products,upgrade the quality of products,and build up branded products.The government should foster the main body of the products andguide the main body to realize the importance of brand construction and management.The second is to construct a sales channel system of greenagricultural products,making use of the trading center of modern green agricultural products to sell products,developing a long term partnershipwith processing industries,big supermarket and restaurants,making use of internet and selling products online and offline.The third is to propagatethe products.Make a good use of advertisement,personal sales,propagation and public relations to accelerate the healthy development of greenagricultural market.

Humidifying Effect of Green Space during Spring in Yuxi Park of Shijiazhuang City of China

As one of the important parts of urban ecosystem, urban green space plays an irreplaceable role in maintaining the balance of carbon and oxygen, absorbing the pollution and removing dust, killing bacteria, purifying soil and water. To analyze the spatio-temporal changes of humidifying effect of green lands at the spring daytime, the authors monitored the air humidity within 1.8 m high from various underlying surfaces, including arbor-grass lands, shrub lands, herb lands and a cement pavement, from late February to late April in 2015 and 2016, when it was sunny and windless, in the Yuxi park of Shijiazhuang. The results were compared with the monitoring data of a bare land(190 m×120 m) without environmental interventions such as vegetation and water. The results could be summarized as follows:(1) The humidifying effect of green spaces was the weakest at 8:00 a.m. during the late February, whereas it was the strongest at 10:00 a.m.; from late March to late April, the humidifying effect of green spaces strengthened with the increase of air temperature, and the strongest was noted around 12:00-16:00.(2) The humidifying effect of various types of green lands was the strongest close to the ground, and reduced from 0.2 m to 1.8 m. This vertical stratification became apparent after the plants sprouted, the vertical difference of humidifying effect was the most significant in the herb lands, less significant in arbor-grass lands, and least in the shrub lands.(3) Multiple comparison analysis of the humidity data showed that relative humidity of all green lands achieved the significant level(P < 0.05), indicating the strong effect of landscape plants in adjusting atmospheric humidity in spring.(4) The humidifying effect of the artificial lake was more remarkable before the plants sprouted, however, with the rapid growth of plant leaves, theeffect gradually reduced and became even weaker than the effect of vegetation. Although the humidifying effect in spring was weaker than that in summer and autumn, the effect of humidification was more complicated during the growth of green leaves in spring than in summer and autumn. This is useful to construct the theory system of ecological environment effect of green lands in spring, summer and autumn.

双碳目标下绿色金融碳减排效应的实证研究

绿色金融是实现绿色低碳发展战略的重要手段,研究绿色金融碳减排效应及其作用机制对实现“双碳”目标具有重要现实意义。利用2008—2020年省际面板数据,实证检验了绿色金融碳减排效应、作用机制和异质性。研究结果表明:无论是总维度还是分维度,绿色金融均具有显著的碳减排效应,其中绿色投资的碳减排效应最大,绿色证券次之,绿色信贷最小;绿色技术创新对绿色金融碳减排效应具有中介作用,环境规制与金融市场化均增强了绿色金融碳减排效果;东部组、科技发达组和高耗能组相对中西部组、科技欠发达组和低耗能组绿色金融碳减排效应更为明显。因此,进一步加大绿色金融产品创新,实现绿色金融资源高效配置,制定差异化绿色金融政策尤为重要。

数字化转型赋能企业绿色创新:监督效应与激励效应的分析

数字化转型是新一轮产业革命驱动下企业的战略选择,为企业绿色创新提供了新动能。以2011—2020年沪深两市A股上市公司为样本,理论分析并实证检验了数字化转型赋能企业绿色创新的作用机制。研究发现:数字化转型可以显著促进企业的绿色创新。该结论在经过一系列稳健性检验后依然成立。机制分析表明,数字化转型驱动企业实施绿色创新主要通过监督效应和激励效应两条路径实现。异质性分析表明,在内部控制质量较好、所处地区市场化水平较高、国有和重点排污企业中,数字化转型产生的绿色创新驱动效应更大。此外,数字化转型推进企业同时开展绿色独立和联合创新、同时积累绿色发明专利和实用新型专利。研究结论明确了数字化转型赋能企业绿色创新的作用机理,为促进企业绿色创新、助力企业高质量发展提供了政策启示。

环境政策与知识产权政策协同对绿色金融发展的影响研究

基于反事实思维,以2006~2019年中国192个城市为样本,运用回归控制法(HCW),实证检验低碳试点城市和知识产权示范城市政策协同对绿色金融的驱动效应,并重点分析政策协同影响绿色金融发展过程中绿色专利信号的传导机制。研究发现:政策协同能够给城市绿色金融发展带来显著正向冲击效应,且这一结论具有较强稳健性;无论是数量维度还是质量维度,政策协同均能在一定程度上强化绿色专利信号,尤其在强化高质量绿色专利信号方面较为突出;仅当绿色专利申请具备一定质量水平时,才能在低碳试点城市与知识产权示范城市政策协同影响绿色金融发展过程中发挥有效的专利信号中介效应。

数字化转型的环境治理效应——来自中国制造业上市公司年报文本分析的证据

随着环境治理绩效的逐步提升,人们对环境质量的渴求也随着碳达峰和碳中和目标的提出而上升至一个新的高度,传统的环境规制手段已很难有更大的突破。已有研究发现数字技术成为推动中国绿色发展的新动力,数字化转型已经成为企业拓展环境绩效边界的重要途径。通过爬虫技术抓取上市企业年报中与“数字化转型”相关的关键词来刻画制造企业数字化转型水平,并基于2008-2020年A股制造业上市公司数据,实证探究了数字化转型对企业环境绩效的影响及其机理。研究发现:制造企业数字化转型显著提升了其环境绩效,并且该结论在考虑内生性问题以及一系列稳健性检验基础上依然成立;机制分析表明,数字化转型对制造企业环境绩效的提升作用主要通过促进企业绿色技术创新和缓解企业内部融资约束来实现;异质性分析发现,数字化转型的环境绩效提升效果不仅受产权性质、企业规模和行业属性等企业内部特征的影响,还受地区环境规制强度等外部因素的影响。因此应进一步推动企业数字化转型,加强企业环境信息披露,强化数字技术对企业环境绩效的治理效应。

供应链联动下企业数字化的绿色创新外溢效应

企业数字化转型是推动经济高质量发展的重要举措,供应链上下游企业数字化联动能否推动企业绿色发展值得深入探究。基于供应链联动效应,研究了供应链上下游企业数字化转型对焦点企业绿色创新的外溢效应及作用机制。研究发现:上下游企业数字化转型对焦点企业绿色创新存在显著正向影响,且该结论在安慰剂、工具变量等一系列稳健性检验后依然显著成立;其中,上游供应商数字化转型对于焦点企业绿色创新的影响更加显著,供应链企业数字化转型的绿色创新外溢效应主要体现为上游企业的技术推动。机制检验表明,上下游企业数字化转型通过供应链内部企业学习、供应链外部主体关注提升了焦点企业绿色创新水平。异质性检验表明,当焦点企业与上下游企业所属行业不同、地理距离较近时,上下游企业数字化转型对焦点企业绿色创新发挥的外溢效应更显著。最后,研究发现上下游企业数字化转型在促进焦点企业绿色创新产出中发挥了“杠杆效应”,刺激企业要素投入增加的同时还提升了绿色创新效率。研究结论为推动数字化绿色供应链建设提供了启示。

农业保险、农业规模经营与农业绿色发展

农业保险对农业现代化发展具有重要影响。文章从农业保险影响农业规模经营、产生增收效应和环境效应入手,采用2007—2021年省级面板数据,分析农业保险通过农业规模经营对农业绿色发展产生的影响。研究表明:农业保险是推动农业规模经营并促进农业绿色发展的重要因素;农业规模经营是农业保险助推农业绿色发展的中介机制;多维环境效应研究表明,农业保险对农业碳排放、农业化肥面源污染有重要影响;农民收入水平较低和农作物种植规模较高的地区,农业保险更有利于推动农业绿色发展。由此,提出充分发挥农业保险优势、促进农业绿色发展的建议。

空间溢出视角下旅游发展的绿色经济效应检验与分析

旅游业的发展对建设美丽中国和贯彻生态文明战略至关重要,研究旅游发展的绿色经济效应具有必要的理论意义和现实意义。文章以2007—2019年中国280个地级市为研究对象,从空间溢出视角对旅游发展的绿色经济效应进行检验,进一步分析其空间异质性和效应边界。结论如下:(1)观察期内,我国城市绿色经济效率波动上升,效率分布呈“东部>西部>东北>中部”格局,“中部塌陷”特征明显;在考虑地理距离、经济距离和经济地理距离的情况下,旅游发展的绿色经济效应稳健性表现为溢出效应而非本地效应。(2)绿色经济效应空间异质性明显,溢出绿色经济效应呈中部>东北>东部>西部格局,西部本地和溢出绿色经济效应均显著,中部本地绿色经济效应表现为负向;效应不存在城市群和非城市群边界,均以溢出绿色经济效应为主。(3)绿色经济效应存在地理边界,1300千米后本地绿色经济效应开始逐渐由负转正,溢出绿色经济效应开始衰减。文章为旅游成为推动区域经济绿色发展的重要途径提供了理论支撑。

全国统一大市场建设的环境效应——基于空间溢出视角

加快建设全国统一大市场是实现高质量发展的必由之路,改善环境质量应是其题中之义。基于2008—2021年我国省级面板数据和空间杜宾模型,研究全国统一大市场建设的环境效应。结果显示,我国环境污染物排放具有显著的空间正相关性,且在能源禀赋丰裕的省份更明显,但整体呈现减弱趋势。全国统一大市场建设对环境污染物排放具有显著的抑制效应和空间溢出效应,经过一系列稳健性检验后,该结论仍然成立。全国统一大市场建设对环境污染物排放存在空间异质性影响:从胡焕庸线区域分割特征来看,与西北片区和东南片区相比,只有对中间地带本地-邻地环境污染物排放的抑制效应显著;从“大气十条”政策实施时期来看,该政策实施后,对环境污染物排放的抑制效应和空间溢出效应均得到显著提升。扩展性研究表明,全国统一大市场建设对实现减污降碳具有协同效应和空间溢出效应。鉴于此,资源型地区应积极加快能源结构转型,大力发展节能环保、新能源等新兴产业,以打破“资源诅咒”、缓解污染集聚。同时,立破并举,加快建设全国统一大市场,灵活设计制度体制,减少制度性交易成本和地方保护主义行为,将财政资金更多地向交通枢纽、网络通信等基础设施倾斜,奠定构建统一大市场和环境治理一体化的基础。此外,坚持全国“一盘棋”,凝练推广如京津冀、长三角、珠三角等现有区域一体化战略的模式经验,遵循共同但有区别原则,形成以中间地带省份为全国统一大市场建设中心、向外围省份延展的建设格局。协同环境政策的导向作用,培育形成统一的生态文明市场,实现绿色高质量发展。