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2.
Sci Rep ; 14(1): 2305, 2024 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280899

RESUMO

This transition from gathering to cultivation is a significant aspect of studying early agricultural practices. Fruit trees are an essential component of food resources and have played a vital role in both ancient and modern agricultural production systems. The jujube (Ziziphus jujuba Mill.), with its long history of cultivation in northern China, holds great importance in uncovering the diet of prehistoric humans and understanding the origins of Chinese agricultural civilization. This paper focuses on the domestication of jujube by analyzing the morphology of jujube stones found in three Neolithic sites in northern China's Qi River basin, Zhujia, Wangzhuang, and Dalaidian. The measurements of these jujube kernels are compared with those found in other areas of northern China, as well as modern jujube kernels that were collected. The measurements revealed that the length-to-diameter (L/D) ratio of sour jujube kernels ranged from 1.36 to 1.78, whereas the L/D ratio of cultivated jujube stones varied between 1.96 and 4.23. Furthermore, jujube stones obtained from Zhujia and Wangzhuang sites exhibit pointed ends and possess an elongated oval or narrow oval shape overall, which is indicative of clearly artificial domestication traits. Therefore, this study suggests that jujube was selected and cultivated as an important food supplement in the Qi River basin no later than around 6200 BP.


Assuntos
Ziziphus , Humanos , Qi , Rios , Frutas , China
3.
Environ Sci Ecotechnol ; 9: 100143, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36157857

RESUMO

Carbamazepine (CBZ), as one of the most frequently detected pharmaceuticals, is of great concern due to its potential impact on the ecosystem and human health. This study provides an effective approach to remove CBZ by using photocatalyst silver phosphate combined with graphene oxide (Ag3PO4/GO) under visible irradiation. The morphology, composition, and optical properties of Ag3PO4/GO were characterized employing SEM, XRD, and DRS. Graphene oxide could improve the visible-light utilization and promote electron's charge to enhance the photocatalytic performance of Ag3PO4/GO. With the optimal reaction condition of 5.86 mW/cm2 light intensity, 15-25 °C temperature, 5-7 pH, and 0.5 mg/L catalytic dosages, 5 mg/L CBZ could be completely degraded in 30 min, and the apparent rate constant could reach 0.12 min-1. Additionally, the radical trapping experiments indicated •OH and O2-• were the main reactive oxygen species employed to eliminate CBZ. The decay pathways of CBZ had been proposed accordingly, and the main product was the low-molecular products.

4.
Sci Rep ; 12(1): 16331, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175486

RESUMO

The region of Transoxiana underwent an early agricultural-demographic transition leading to the earliest proto-urban centers in Central Asia. The agronomic details of this cultural shift are still poorly studied, especially regarding the role that long-generation perennials, such as grapes, played in the cultivation system. In this paper, we present directly dated remains of grape pips from the early urban centers of Sapalli and Djarkutan, in south Uzbekistan. We also present linear morphometric data, which illustrate a considerable range of variation under cultivation that we divide into four distinct morphotypes according to pip shape. While some of the pips in these two assemblages morphologically fall within the range of wild forms, others more closely resemble modern domesticated populations. Most of the specimens measure along a gradient between the two poles, showing a mixed combination of domesticated and wild features. We also point out that the seeds recovered from the Djarkutan temple were, on average, larger and contained more affinity towards domesticated forms than those from domestic contexts. The potential preference of morphotypes seems to suggest that there were recognized different varieties that local cultivators might aware and possibly propagating asexually.


Assuntos
Vitis , Agricultura , Civilização , Sementes , Uzbequistão
5.
ACS Appl Mater Interfaces ; 13(35): 41584-41592, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34433258

RESUMO

Perfluorooctanoic acid (PFOA) has raised significant health concerns due to its high ecotoxicological risks and difficulties in removal by conventional water treatment process. Previous studies have demonstrated that photocatalytic techniques exhibit great potential in PFOA removal. However, the underlying mechanism of the degradation process has not been fully understood, particularly the contribution of the facet effects of catalysts. In this study, a combination of experiments and first-principles calculations were conducted to shed light on the facet-dependence of the interfacial interactions and oxidation during the PFOA degradation process. We proved that the interfacial interaction was essential in initiating the hole-dominated degradation process, and the {110}R3̅c facet of hexagonal In2O3 features the strongest interaction with PFOA. The overall defluorination rate was mainly controlled by the hole-dominated oxidation processes under UV irradiation, which were further attributed to the electronic structures and reaction site distributions of different In2O3 surfaces. This study provides molecular-level insights on the facet-dependent PFOA catalytic degradation process, which can guide the rational design of photocatalysts to achieve superior decontamination efficiency.

6.
Sci Total Environ ; 778: 146383, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030363

RESUMO

In this study, the Songgang River (SR) was selected as a typical contaminated urban river in a highly urbanized city (Shenzhen) that is extensively polluted by heavy metals (HMs). Five representative sampling sites were selected from different urban functional areas along the SR, and the spatial and vertical distributions of HMs and the related environmental risk were investigated. In addition, the distribution variability, composition, and abundance of microbial communities, as well as the correlation between the abundance of the operational taxonomic units (OTUs) and the HM contents were analyzed. The spatial distribution of HMs in the sediment revealed wide variation among the different urban functional areas. Industrial and residential areas had higher HM contents, following the order of Cu > Zn > Ni > Cr > Pb. In addition, the vertical characterization (5-300 cm) of HM content showed a decreasing trend with depth, with a distinct layer around 120-180 cm that might have been caused by anthropogenic activity. An ecological risk assessment indicated that Cu, Ni, and Cr pose high potential risks in these industrial and residential areas (at the depth of 5-180 cm). Furthermore, microbial community analysis indicated that some HM-tolerant bacteria (e.g., Gallionella, Acidovorax, Arenimonas, Curvibacter, and Sideroxydans) were dominant in the 5-120 cm layer, corresponding to high HM contents. A canonical correspondence analysis and co-occurrence network further confirmed that there was a strong correlation among the urban functional areas, HM contents, and the abundance of microorganisms in the urban river sediment. The results of this study have the potential to provide a bio-augmentation strategy for the in-situ bioremediation of sediment contaminated by HMs.


Assuntos
Metais Pesados , Microbiota , Poluentes Químicos da Água , China , Cidades , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise
7.
Sci Rep ; 10(1): 21548, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33299055

RESUMO

Iodinated contrast media (ICM), which was widely used in medical imaging and was difficult to remove by conventional wastewater treatment methods, attained much attention due to its potential environmental impacts. Herein, iopamidol (IPM), one typical compound of ICM, was found to be rapidly degraded by ferrous activated persulfate oxidation (Fe(II)/PS) as compared with PS or Fe(II) alone. With a persulfate concentration of 1 mmol L-1, n(Fe(II))/n(PS) of 1:10, and a pH of 3.0, 78% IPM was degraded within 60 min, with a degradation rate of 0.1266 min-1. It was demonstrated that IPM degradation and deiodination were favored by a high temperature, while affected positively by acidic and neutral conditions. Radical quenching experiments and Electron Paramagnetic Resonace (EPR) spectra showed that the combined effects of SO4-· and ·OH contributed dominantly to degrade IPM, while the ·OH played an essential role during the degradation reaction. Through the Discrete Fourier Transform quantum chemical calculation, the possible reaction pathways for the oxidation of IPM by ·OH are as follows: IPM-TP651-TP667-TP541-TP557, IPM-TP651-TP525-TP557, IPM-TP705-TP631-TP661, and IPM-TP705-TP735. The obtained results showed that IPM could be degraded effectively by Fe(II)/PS system, giving a promising technique for IPM removal from water.

8.
Environ Pollut ; 266(Pt 1): 115360, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32836015

RESUMO

In this study, the Songgang River (SR) was selected as a typical tributary that is heavily polluted by rapid urbanization and industrialization. The polycyclic aromatic hydrocarbon (PAH) distribution at five representative sampling sites from different urban functional areas was studied. The chemical and physical properties and spatial and vertical distribution of PAHs in sediments were investigated. PAH source identification and the ecological risks of the sediments were evaluated. The results suggested that the industrial zone and dense residential and commercial areas were the most contaminated areas of the SR, as the chemical and physical properties of total organic carbon content in sediments was the highest at the dense residential and commercial areas (0.1-4.5%); however, the acid volatile sulfide, total nitrogen, and total phosphorus contents were the highest in the industrial zone, with ranges of 700.0-1618.4 mg/kg dw, 22.4-3543.9 mg/kg dw, and 82.3-4550.7 mg/kg dw, respectively. The spatial distribution of residual PAHs in the sediment cores showed a wide variation among different urban functional areas, and the vertical characterization (0-300 cm) depicted a significant decreasing trend with depth and with an abrupt increase at 180 cm. The concentration of ∑16 PAHs ranged from 208.7 to 7709.8 ng/g dw, with the highest concentrations obtained in the industrial zone. The low molecular weight-PAHs (153-6720 ng/g dw) were predominant in the sediments. Furthermore, there were combined sources (biomass burning: 40.3%; fossil fuel combustion: 25.5%; mixed source: 21.5%; oil pollution: 12.7%) and a long term accumulation effect, with anthropogenic activities and industrial pollution as the major contributing sources. The concentrations of Nap, Acy, Ace, Flu, and Ant exceeded the lower limit of the sediment quality criteria, and higher toxic equivalent concentration values of the total carcinogenic PAHs were observed nearby the midstream of the SR, which may cause adverse biological effects and implies a need for regular monitoring.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Sedimentos Geológicos , Medição de Risco
9.
Nat Plants ; 6(2): 78-87, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32055044

RESUMO

Wheat and barley evolved from large-seeded annual grasses in the arid, low latitudes of Asia; their spread into higher elevations and northern latitudes involved corresponding evolutionary adaptations in these plants, including traits for frost tolerance and shifts in photoperiod sensitivity. The adaptation of farming populations to these northern latitudes was also a complex and poorly understood process that included changes in cultivation practices and the varieties of crops grown. In this article, we push back the earliest dates for the spread of wheat and barley into northern regions of Asia as well as providing earlier cultural links between East and West Asia. The archaeobotanical, palynological and anthracological data we present come from the Tongtian Cave site in the Altai Mountains, with a punctuated occupation dating between 5,200 and 3,200 calibrated years BP, coinciding with global cooling of the middle-late Holocene transition. These early low-investment agropastoral populations in the north steppe area played a major role in the prehistoric trans-Eurasian exchange.


Assuntos
Agricultura , Grão Comestível , Hordeum , Dispersão Vegetal , Triticum , Arqueologia , China , Produtos Agrícolas , Migração Humana
10.
J Hazard Mater ; 350: 128-135, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29466779

RESUMO

This research explored the application of electro-Fenton (E-Fenton) technique for the simultaneous decomplexation in blended Cu(II)/Ni(II)-EDTA systems by using iron sacrificing electrodes. Standard discharge (0.3 mg L-1 for Cu and 0.1 mg L-1 for Ni in China) could be achieved after 30 min reaction under the optimum conditions (i.e. initial solution pH of 2.0, H2O2 dosage of 6 mL L-1 h-1, current density of 20 mA/cm2, inter-electrode distance of 2 cm, and sulfate electrolyte concentration of 2000 mg L-1). The distinct differences in apparent kinetic rate constants (kapp) and intermediate removal efficiencies corresponding to mere and blended systems indicated the mutual promotion effect toward the decomplexation between Cu(II) and Ni(II). Massive accumulation of Fe(Ⅲ) favored the further removal of Cu(II) and Ni(II) by metal ion substitution. Species distribution results demonstrated that the decomplexation of metal-EDTA in E-Fenton process was mainly contributed to the combination of various reactions, including Fenton reaction together with the anodic oxidation, electro-coagulation (E-coagulation) and electrodeposition. Unlike hypophosphite and citrate, the presence of chlorine ion displayed favorable effects on the removal efficiencies of Cu(II) and Ni(II) at low dosage, but facilitated the ammonia nitrogen (NH4+-N) removal only at high dosage.

11.
Chemosphere ; 180: 48-56, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28391152

RESUMO

Elimination of hypophosphite (HP) was studied as an example of nickel plating effluents treatment by O3/H2O2 and sequential Fe(II) catalytic oxidation process. Performance assessment performed with artificial HP solution by varying initial pH and employing various oxidation processes clearly showed that the O3/H2O2─Fe(II) two-step oxidation process possessed the highest removal efficiency when operating under the same conditions. The effects of O3 dosing, H2O2 concentration, Fe(II) addition and Fe(II) feeding time on the removal efficiency of HP were further evaluated in terms of apparent kinetic rate constant. Under improved conditions (initial HP concentration of 50 mg L-1, 75 mg L-1 O3, 1 mL L-1 H2O2, 150 mg L-1 Fe(II) and pH 7.0), standard discharge (<0.5 mg L-1 in China) could be achieved, and the Fe(II) feeding time was found to be the limiting factor for the evolution of apparent kinetic rate constant in the second stage. Characterization studies showed that neutralization process after oxidation treatment favored the improvement of phosphorus removal due to the formation of more metal hydroxides. Moreover, as a comparison with lab-scale Fenton approach, the O3/H2O2─Fe(II) oxidation process had more competitive advantages with respect to applicable pH range, removal efficiency, sludge production as well as economic costs.


Assuntos
Ácidos Fosfínicos/química , Poluentes Químicos da Água/química , Catálise , China , Compostos Ferrosos/química , Peróxido de Hidrogênio/química , Metalurgia , Oxirredução , Ozônio/química , Esgotos , Eliminação de Resíduos Líquidos/métodos
12.
Huan Jing Ke Xue ; 35(6): 2249-55, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25158503

RESUMO

Based on the comparison of phosphorous removal in sludge water and its supernatant by polyaluminum chloride (PAC), separate and combined effects of Al/P mole ratio, pH and mixing speed (MS) on phosphorus removal by PAC for the supernatant of thickening and dewatering sludge water were analyzed by the response surface methodology (RSM), and kinetics of phosphorous removal by PAC was also investigated. The results showed that direct addition of PAC into sludge water deteriorated its settling characteristics, and suspended solids in the sludge water could decrease the phosphorus removal efficiency. The RSM analysis results demonstrated that the effect of individual operation parameter on phosphorus removal was followed as the order of Al/P > pH > MS, and the optimal process parameters with phosphorus removal efficiency of 97.8% were Al/P = 2.49, pH = 8.3 and MS 398 r x min(-1), respectively. The verification experiment showed that the RSM model was valid and effective. Kinetic analysis illustrated that phosphorus removal by PAC was divided into two stages, a chemical precipitation and rapid adsorption stage, followed by a chemical precipitation stage that conformed to the second-order kinetics.


Assuntos
Hidróxido de Alumínio/química , Fósforo/análise , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Adsorção , Precipitação Química , Cinética , Água/química
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