This paper assesses the spatial effects of environmental regulations on economic activities. By exploiting the progressive rollout of a national pollution control program in China, which constructed a monitoring network that covered the urban center of every city, we find that polluting firms located in the unmonitored upwind region of the city experienced a substantially larger reduction in output than non-upwind firms after the program. Because the wind can transport upwind pollution emissions to the monitoring network-covered urban center, local governments are incentivized to enforce tighter regulations on upwind firms. Although industrial activities were suppressed, commercial businesses and residential services were promoted in the upwind region, accompanied by a greater supply of corresponding land and increased land prices. Altogether, the monitoring program led to a substantial reduction in population exposure to air pollution and an redistribution of industrial and residential activities within the city. Our findings shed light on the policy-making of future environmental regulation programs.
Lowland multi-channel alluvial river systems are highly variable in frequency and magnitude of floodplain inundation and are vulnerable to human activities such as damming. In the Yangtze River Basin, the Three Gorges Dam (TGD) has trapped >80% of upstream sediment supply, causing downstream scouring and rapid geomorphic changes in river and its floodplain lakes. Suspended sediment concentration (SSC) is widely used to monitor river morphodynamics, but traditional measurements of SSC are time consuming, costly and difficult to quantify SSC in a large spatial scale. Using Google Earth Engine and in situ observed hydrological data, we created a multiple linear regression model to map SSC in the multi-channel system Songzi River of the Yangtze. The new SSC predictive model achieved high accuracy (R2: 0.87) and showed opposite downstream trends in SSC during peak flood years and normal flood years. For the first time, we found that in the peak flood year of 1998 the study rivers exhibit a downstream increase trend of SSC with an abrupt increase in their middle reach, while SSC in normal flood years experiences a downstream decline with minimal changes. A prominent difference in SSC is also revealed after the TGD with a reduction of 60%. Furthermore, SSC in the closely hydrologically connected lakes is more dynamic than the less connected lakes. Our study demonstrates that the proposed method enables to rapidly quantify the spatio-temporal SSC distribution in the multi-channel systems on the floodplain of large alluvial rivers and highlights the importance of connectivity in regulating SSC dynamics.
This paper looks at how the Ephesian gubernatorial edict (Ephesos 231 = IK 12.215 p. 27) found near Magnesia ad Maenandrum can be an adequate response to a state of public disorder (ταραχή) and madness (ἀπονοία) caused by bakers refusing to supply the city with the necessary production of bread. The goal of the gubernatorial edict was to restore sense to the demos by edict (διατάγματι σωφρονίζειν) without having to arrest, try, and punish offenders. Specific measures include forbidding bakers to gather according to association (μήτε συνέρχεσθαι κατ᾽ ἑταίρα), and forbidding those who stood as bakers' representatives from behaving rashly (μήτε προεστηκότας θρασύνεσθαι), along with the specific demand that leaders are to obey authority (πειθαρχεῖν) and produce bread. The reference to an agreement, and the subsequent result clause, may suggest that one party to the agreement defaulted and led to widespread discontent, though the fragmentary nature of the inscription makes it difficult to speculate further. But the edict only resorted to banning gatherings, with no comment on the root causes of dissent. Additional assistance provided by the boule would have been necessary and likely given, though the part of the stone has been lost. Recent discussions on how governors dealt with issues pertaining to public order (Fuhrmann 2012) and the eirenarchate (Rife 2002) can be of some guidance. In addition, this paper explores mechanisms and tools accessible to praesidial governors based on the corpus of known gubernatorial edicts collected as part of a larger project to consider possible scenarios.
Antibiotics have been widely used to treat bacterial diseases. Their wide spread in ecological environment will induce generation of antibiotic-resistant bacteria Therefore, it is critical to create an eco-friendly and effective approach for their removal. Herein, a bimetallic sulfide FeS2@MoS2 with rich sulfur vacancies (SVs) and high percentage of metallic 1T phase MoS2 was prepared by one-step solvothermal method to degrade ofloxacin (OFX) by activated peroxymonosulfate (PMS). FeS2@MoS2-1 (the mass ratio of Fe/Mo is 1) exhibited excellent performance for PMS activation, with 99.26% OFX removed in 20 min (0.2 g/L FeS2@MoS2-1, 0.2 mM PMS, initial pH). The degradation rate constant of kobs was 0.21 min−1 with FeS2@MoS2-1 system, which was about 4.88 and 22.91 times of FeS2/PMS and MoS2/PMS systems under the same experimental conditions respectively. In FeS2@MoS2-1, besides S2−, SVs would also accelerate Fe(III)/Fe(II) circulation through increasing the exposure of Mo(IV) active sites. Additionally, MoS2 transferred from the semi-conductive 2H phase to the metallic 1T phase, which could speed up electron transfer rate significantly. Quenching experiment and EPR test showed that SO4− and O2− were the main active oxygen species. Degradation pathway was proposed through the active sites identification by DFT calculations and intermediates detection by HPLC-MS analyzation. The results showed that OFX were vulnerable to be attacked and broke to form small molecular compounds through hydrogen loss, oxidative cracking, decarboxylation and demethylation four ways. In addition, their bio-toxicity was investigated and results showed that the toxic was diminished. This work indicated that the satisfactory universality, recyclability and stability enabled FeS2@MoS2-1 could be used as an efficient catalyst to activate PMS to degrade refractory organic pollutants in water.
The rapid development of high-speed rail has markedly shortened the travel time from one city to another. However, the impact of space–time compression brought about by high-speed rail on city innovation has not received sufficient attention. This paper examines the space–time compression phenomenon produced by high-speed railway networks and its impact on city innovation from 2000 to 2019 using a sample of 279 Chinese prefecture-level cities. The empirical results show that there was a strong space–time compression during this period. The development of high-speed rail can promote city innovation. However, the construction of high-speed rail also produces a siphon effect, which accelerates the convergence of innovative elements in cities with stronger innovation capabilities. Nevertheless, it has a negative spillover effect on cities with weaker innovation capabilities. Finally, policy recommendations for promoting the balanced development of city innovation and recommendations for future research are presented.
Governmental investment in commercializing academic patents has spurred economic growth. This study explores the mechanism underlying the impact of academic patent commercialization on regional economic development based on holistic view of the integration of local and neighbourhood hierarchies. The empirical analysis of a sample of 31 Chinese provinces from 2010 to 2019 shows that fiscal expenditures on science and technology mediate the relationship between academic patent commercialization and economic development. Moreover, there is a positive spatial spill over effect between developing economies of neighbouring provinces. In the knowledge economy era, academic patent commercialization, supported by fiscal expenditure, plays an increasingly important role in regional economic growth.