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831.
A series of cobalt doped TiO_2(Co-TiO_2) and Co Oxloaded TiO_2(Co/TiO_2) catalysts prepared by sol–gel and impregnation methods respectively were investigated on selective catalytic reduction with NH_3(NH_3-SCR) of NO. It was found that Co-TiO_2 catalyst showed more preferable catalytic activity at low temperature range. From characterization results of XRD,TEM, Raman and FT-IR, Co species were proved to be doped into TiO_2 lattice by replaced Ti atoms. After being characterized and analyzed by NH_3-TPD, PL, XPS, EPR and DRIFTS, it was found that the better NH_3-SCR activities of Co-TiO_2 catalysts, compared with Co/TiO_2 catalyst, were ascribed to the formation of more oxygen vacancies which further promoted the production of more superoxide ions(O-2). The superoxide ions were crucial for the formation of low temperature SCR reaction intermediates(NO-3) by reacting with adsorbed NO molecule. Therefore, these aspects were responsible for the higher low temperature NH_3-SCR activity of Co-TiO_2 catalysts.  相似文献   
832.
正Swimming is excellent exercise and offers many health benefits.However,the"chlorine smell"in swimming pools may be a turn-off for some people.Although this smell is often thought to be of chlorine,it actually comes from volatile compounds that are produced from unintended reactions between disinfectants(e.g.,chlorine)and organic matter in  相似文献   
833.
Adsorption and desorption are important processes that affect atrazine transport,transformation,and bioavailability in soils.In this study,the adsorption–desorption characteristics of atrazine in three soils(laterite,paddy soil and alluvial soil) were evaluated using the batch equilibrium method.The results showed that the kinetics of atrazine in soils was completed in two steps:a"fast" adsorption and a "slow" adsorption and could be well described by pseudo-second-order model.In addition,the adsorption equilibrium isotherms were nonlinear and were well fitted by Freundlich and Langmuir models.It was found that the adsorption data on laterite,and paddy soil were better fitted by the Freundlich model;as for alluvial soil,the Langmuir model described it better.The maximum atrazine sorption capacities ranked as follows:paddy soil alluvial soil laterite.Results of thermodynamic calculations indicated that atrazine adsorption on three tested soils was spontaneous and endothermic.The desorption data showed that negative hysteresis occurred.Furthermore,lower solution pH value was conducive to the adsorption of atrazine in soils.The atrazine adsorption in these three tested soils was controlled by physical adsorption,including partition and surface adsorption.At lower equilibrium concentration,the atrazine adsorption process in soils was dominated by surface adsorption;while with the increase of equilibrium concentration,partition was predominant.  相似文献   
834.
Environmental Science and Pollution Research - Iron (Fe) fertilizer can reduce cadmium (Cd) uptake and toxicity in rice, but the underlying mechanisms of Cd mitigation by different fertilizers are...  相似文献   
835.
Environmental Science and Pollution Research - Urbanization in China has dramatically increased from 39.10 in 2002 to 58.52% in 2017. Studies have discussed the impacts of urbanization and its...  相似文献   
836.
Environmental Science and Pollution Research - Heavy metal (HM) pollution in orchards is becoming serious in many countries, and some fruit HMs exceed the safety limits. In this study, contents of...  相似文献   
837.
Environmental Science and Pollution Research - A large amount of fresh tobacco waste with high water content are produced in farmland, and it may cause environmental pollution if it is not properly...  相似文献   
838.

Nowadays, the market competition becomes increasingly fierce due to diversified customer needs, stringent environmental requirements, and global competitors. One of the most important factors for companies to not only survive but also thrive in today’s competitive market is their logistics performance. This paper aims, through a systematic literature analysis of 115 papers from 2012 to 2020, at presenting quantitative insights and comprehensive overviews of the current and future research landscapes of sustainable logistics in the Industry 4.0 era. The results show that Industry 4.0 technologies provide opportunities for improving the economic efficiency, environmental performance, and social impact of logistics sectors. However, several challenges arise with this technological transformation, i.e., trade-offs among different sustainability indicators, unclear benefits, lifecycle environmental impact, inequity issues, and technology maturity. Thus, to better tackle the current research gaps, future suggestions are given to focus on the balance among different sustainability indicators through the entire lifecycle, human-centric technological transformation, system integration and digital twin, semi-autonomous transportation solutions, smart reverse logistics, and so forth.

  相似文献   
839.
Soils and waters are heavily contaminated by antimony in Xikuangshan(XKS) mine area.It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment.Bosea sp. AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine. Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes,antimony(Sb) metabolism genes and carbon fixation genes in AS-...  相似文献   
840.
Cobalt iron spinel (CoFe2O4) has been considered as a good heterogeneous catalysis to peroxymonosulfate (PMS) in the degradation of persistent organic pollutants due to its magnetic properties and good chemical stability. However, its catalytic activity needs to be further improved. Here, a facial strategy, “in-situ substitution”, was adopted to modify CoFe2O4 to improve its catalytic performance just by suitably increasing the Co/Fe ratio in synthesis process. Compared with CoFe2O4, the newly synthesized Co1.5Fe1.5O4, could not only significantly improve the degradation efficiency of phenol, from 50.69 to 93.6%, but also exhibited more effective mineralization ability and higher PMS utilization. The activation energy advantage for phenol degradation using Co1.5Fe1.5O4 was only 44.2 kJ/mol, much lower than that with CoFe2O4 (127.3 kJ/mol). A series of related representations of CoFe2O4 and Co1.5Fe1.5O4 were compared to explore the possible reasons for the outstanding catalytic activity of Co1.5Fe1.5O4. Results showed that Co1.5Fe1.5O4 as well represented spinel crystal as CoFe2O4 and the excess cobalt just partially replaced the position of iron without changing the original structure. Co1.5Fe1.5O4 had smaller particle size (8.7 nm), larger specific surface area (126.3 m2/g), which was more favorable for exposure of active sites. Apart from the superior physical properties, more importantly, more reactive centers Co (Ⅱ) and surface hydroxyl compounds generated on Co1.5Fe1.5O4, which might be the major reason. Furthermore, Co1.5Fe1.5O4 behaved good paramagnetism, wide range of pH suitability and strong resistance to salt interference, making it a new prospect in environmental application.  相似文献   
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