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1.
Int J Mol Sci ; 24(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37047349

RESUMO

To fully explore the influence mechanism of interactions between different monomer units of proanthocyanidins (PAs) on biological activity, a path analysis model of the PA structure-activity relationship was proposed. This model subdivides the total correlation between each monomer unit and activity into direct and indirect effects by taking into account not only each monomer unit but also the correlation with its related monomer units. In addition, this method can determine the action mode of each monomer unit affecting the activity by comparing the direct and total indirect effects. Finally, the advantage of this model is demonstrated through an influence mechanism analysis of Rhodiola crenulata PA monomer units on antioxidant and anti-diabetes activities.


Assuntos
Proantocianidinas , Rhodiola , Proantocianidinas/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia
2.
Molecules ; 27(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35956808

RESUMO

Compared to the traditional processing method, fresh processing can significantly enhance the preservation of biologically active ingredients and reduce processing time. This study evaluated the influences of fresh and traditional processing based on different drying conditions (sun drying, oven drying and shade drying) on the active ingredients in the roots and rhizomes of S. miltiorrhiza. High-performance liquid chromatography (HPLC) was utilized to determine the contents of six active ingredients in the roots and rhizomes of S. miltiorrhiza. The data were analyzed by fingerprint similarity evaluation, hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results suggest that compared to the traditional processing method, the fresh processing method may significantly increase the preservation of biologically active ingredients. Furthermore, the findings demonstrated that among the three drying methods under fresh processing conditions, the shade-drying (21.02-26.38%) method is most beneficial for retaining the active ingredients in the roots and rhizomes of S. miltiorrhiza. Moreover, the fingerprint analysis identified 17 common peaks, and the similarity of fingerprints among samples processed by different methods ranged from 0.989 to 1.000. Collectively, these results suggest novel processing methods that may improve the yield of active ingredients for S. miltiorrhiza and may be implemented for industrial production.


Assuntos
Salvia miltiorrhiza , Cromatografia Líquida de Alta Pressão/métodos , Dessecação , Raízes de Plantas/química , Rizoma , Salvia miltiorrhiza/química
3.
Nanotechnology ; 32(41)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-33752183

RESUMO

An integration strategy of chemical welding and subsequent protection was demonstrated to address silver nanowires (Ag NWs)-based issues. Preferentially, a halogenated salt of NaCl solution was used to stimulate the junction welding thus to reduce the junction resistance, by virtue of the autocatalytic redox of Ag atoms with halogen ions and dissolved oxygen molecules. Subsequently, chitosan, possessing the biocompatible, degradable, environmentally friendly non-toxic features, was embedded to protect Ag NWs. With these two steps, the composite electrode consisting Ag NWs and chitosan reaches a lowest sheet resistance of ∼8 Ω, with a transmittance over 80% at 550 nm, along with high thermal and chemical stabilities, accompanying with excellent flexibility. Besides, it also prompts a synergistic improvement when pioneered in Cu(In, Ga)Se2(CIGS) device as a transparent conductive electrode. It yields a power conversion efficiency of 6.6%, with 32% improvement relative to that bare Ag NWs, and 85% of the conventional one. Our findings present a new strategy for addressing instable/inefficient Ag NWs-based devices, driving their rapid development and its practical applications.

4.
Molecules ; 26(9)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919259

RESUMO

Proanthocyanidins are natural glycosidase inhibitors with excellent antioxidant activity. This study aims to search for a new source of proanthocyanidins for the prevention and treatment of type 2 diabetes with higher content and better activity and get their structure elucidated. First, the total proanthocyanidins contents (TOPCs), antioxidant activity, antidiabetic activity of seven common Polygonaceae plants were analyzed and compared. Then proanthocyanidins from the rhizome of Fagopyrum dibotrys were purified, and the detailed structure was comprehensively analyzed by ultraviolet visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), 13C nuclear magnetic resonance spectroscopy (13C NMR), reversed-phase high-performance liquid chromatography-electrospray mass spectrometry (RP-HPLC-ESI-MS), and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). The rhizome of F. dibotrys showed the highest TOPCs, the strongest antioxidant, and antidiabetic activities; the TOPCs, antioxidant and antidiabetic activities were all very significantly positively correlated. Proanthocyanidins purified from the rhizome of F. dibotrys showed better antidiabetic activity than grape seed proanthocyanidins (GsPs). Seventy-two proanthocyanidins from trimer to undecamer with a mean degree of polymerization (mDP) of about 5.02 ± 0.21 were identified with catechin and epicatechin as the dominant monomers. Conclusion: Proanthocyanidins are the main antioxidant and antidiabetic active substances of F. dibotrys and are expected to be developed into potential antioxidant and hypoglycemic products.


Assuntos
Antioxidantes/farmacologia , Fagopyrum/química , Hipoglicemiantes/farmacologia , Proantocianidinas/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Rizoma/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
BMC Genomics ; 21(1): 727, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33106159

RESUMO

BACKGROUND: Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants with high medicinal value. Gibberellins are growth-promoting phytohormones that regulate numerous growth and developmental processes in plants. However, their role on the secondary metabolism regulation has not been investigated. RESULTS: In this study, we found that gibberellic acid (GA) can promote hairy roots growth and increase the contents of tanshinones and phenolic acids. Transcriptomic sequencing revealed that many genes involved in the secondary metabolism pathway were the GA-responsive. After further analysis of GA signaling pathway genes, which their expression profiles have significantly changed, it was found that the GRAS transcription factor family had a significant response to GA. We identified 35 SmGRAS genes in S. miltiorrhiza, which can be divided into 10 subfamilies. Thereafter, members of the same subfamily showed similar conserved motifs and gene structures, suggesting possible conserved functions. CONCLUSIONS: Most SmGRAS genes were significantly responsive to GA, indicating that they may play an important role in the GA signaling pathway, also participating in the GA regulation of root growth and secondary metabolism in S. miltiorrhiza.


Assuntos
Giberelinas , Salvia miltiorrhiza , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Salvia miltiorrhiza/genética , Transcriptoma
6.
Int J Mol Sci ; 20(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064132

RESUMO

Flavonoids play multiple roles in plant coloration and stress resistance and are closely associated with human health. Flavonoids and non-flavonoids (such as phenolic acids) are produced via the phenylpropanoid-derived pathway. Anthocyanidin synthase (ANS) catalyzes the synthesis of anthocyanins from leucoanthocyanidin in the flavonoids branched pathway. In this study, SmANS from Salvia miltiorrhiza was cloned and mainly localized in the endoplasmic reticulum (ER), plastids, Golgi, plasma membrane, and nucleus of tobacco epidermal cells, and was most highly expressed in purple petals in S. miltiorrhiza, whereas it showed almost no expression in white petals, green calyxes, and pistils in S. miltiorrhiza Bge f. alba. Overexpressed SmANS enhanced anthocyanin accumulation but reduced salvianolic acid B (SAB) and rosmarinic acid (RA) biosynthesis in S. miltiorrhiza and S. miltiorrhiza Bge f. alba plantlets, meanwhile, it restored the purple-red phenotype in S. miltiorrhiza Bge f. alba. These changes were due to reallocation of the metabolic flow, which was influenced by the SmANS gene. These findings indicate that SmANS not only plays a key role in anthocyanin accumulation in S. miltiorrhiza, but also acts as a "switch" for the coloration of S. miltiorrhiza Bge f. alba. This study provides baseline information for further research on flavonoids metabolism and improvement of anthocyanin or phenolic acid production by genetic engineering.


Assuntos
Antocianinas/biossíntese , Hidroxibenzoatos/metabolismo , Oxigenases/genética , Proteínas de Plantas/genética , Salvia miltiorrhiza/genética , Oxigenases/metabolismo , Proteínas de Plantas/metabolismo , Salvia miltiorrhiza/metabolismo
7.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4830-4836, 2019 Nov.
Artigo em Zh | MEDLINE | ID: mdl-31872589

RESUMO

GRAS transcription factors play important roles in the regulation of plant root growth and GA signaling. In this study,SmGRAS3 gene was cloned,which open reading frame was 2 247 bp,and encoding 748 amino acids. The physicochemical properties and structure of SmGRAS3 and its encoded protein were analyzed by bioinformatics software. This gene belongs to the SCL9 subfamily of the GRAS family,and its promoter sequence mainly contains the light response,stress response,and hormone response elements. It may interact with the GA signal pathway and anti-stress related proteins. The subcellular localization showed that SmGRAS3 protein was mainly located in the nucleus. The expression pattern analysis showed that the expression of Sm GRAS3 was the highest in the root and the lowest in the stem,and both light and low temperature could induce the high expression level of SmGRAS3. This study provides a foundation for further study on the roles of SmGRAS3 gene in the root growth and stress tolerance of Salvia miltiorrhiza.


Assuntos
Salvia miltiorrhiza/genética , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Fatores de Transcrição
8.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2038-2045, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-31355558

RESUMO

The family of flavonoid 3-O-glucosyltransferase catalyzes the modification of anthocyanin from unstable-structure to stable-structure. In this study,based on homology cloning and transcriptome library,we isolated the full-length c DNA of UDP-glucose: flavonoid 3-O-glucosyltransferase( named SmUF3GT) from the flower tissues of S. miltiorrhiza. This gene was consisted of 1 353 bp open reading frames( ORF) encoding 450 amino acids. And the SmUF3GT protein was performed for the bioinformatic analysis. Our results showed that the protein was preliminary localized in the Golgi and peroxisome of cytosol,as well as plasma membrane and cell nuclear.QRT-PCR analyses indicated that SmUF3GT expressed differently in all tissues and organs but roots of S. miltiorrhiza and S. miltiorrhiza f.alba. During floral development,the expression of SmUF3GT showed a trend of rising fist and then down in purple-flower Danshen,whereas decreasing sharply fist and then slowly in white-flower Danshen. The present study provides basic information for further research on the network of synthesis and accumulation of flavonoids in S.miltiorrhiza.


Assuntos
Glucosiltransferases/genética , Proteínas de Plantas/genética , Salvia miltiorrhiza/genética , Clonagem Molecular , Flores/enzimologia , Regulação da Expressão Gênica de Plantas , Fases de Leitura Aberta , Salvia miltiorrhiza/enzimologia
9.
Environ Geochem Health ; 40(5): 1965-1978, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28573332

RESUMO

With the enhancement of human activities which influence the physical and chemical integrity of ecosystem, it was bound to increase ecological risk to the ecosystem, and the risk assessment of small scale, single pollutant, or only on water quality have been not satisfied the demand of sustainable development of basin water environment. Based on the response relationship between environmental flow requirements guarantee ratio (GEF) and river ecological risk index (ERI), the Sediment Quality Guideline Quotient index (SQG-Q), and the Biotic Index (BI), we construct a new comprehensive ecological risk index (CERI) to evaluate the ecological risk of Luanhe River, China. According to the response relationship between GEF and ERI, upper and lower reaches of Luanhe River (Goutaizi to Hanjiaying) were at moderate risk level (0.41 < ERI < 0.56) in dry season, and all sites were at low risk level (ERI < 0.40) in wet season; considering the contribution of heavy metals contamination in the SQG-Q, the Luanhe River was the most influenced by higher levels of heavy metals in dry season and wet season; when this index was applied to the PAHs levels, only 30 and 20% of the sampling sites appeared to be moderately impacted (0.1 < SQG-Q PAHs < 0.5) by the PAHs in dry season and wet season, respectively. The results of BI showed that half of the sites appeared to be at moderately polluted level (50% of the sites, 0.25 < BI < 0.32) and heavily polluted level (Zhangbaiwan, BI = 0.36) in dry season, and 40% of the sites appeared to be at moderately polluted level (0.26 < BI < 0.29) in wet season. The CERI showed that 70 and 30% of the sites were at moderate risk level in dry season (0.25 < CERI < 0.36) and wet season (0.26 < CERI < 0.29), respectively. The results could give insight into risk assessment of water environment and decision-making for water source security.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Medição de Risco/métodos , Poluentes Químicos da Água/análise , China , Ecologia , Ecossistema , Humanos , Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Estações do Ano , Qualidade da Água
10.
Cell Physiol Biochem ; 43(4): 1487-1502, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29035891

RESUMO

BACKGROUND/AIMS: Autophagy modulation has been considered a potential therapeutic strategy for human chondrosarcoma, and a previous study indicated that salidroside exhibits significant anti-carcinogenic activity. However, the ability of salidroside to induce autophagy and its role in human chondrosarcoma cell death remains unclear. METHODS: We exposed SW1353 cells to different concentrations of salidroside (0.5, 1 and 2 mM) for 24 h. RT-PCR, Western-blotting, Immunocytofluorescence, and Luciferase Reporter Assays were used to evaluate whether salidroside activated the TFEB-dependent autophagy. RESULTS: We show that salidroside induced significant apoptosis in the human chondrosarcoma cell line SW1353. In addition, we demonstrate that salidroside-induced an autophagic response in SW1353 cells, as evidenced by the upregulation of LC3-II and downregulation of P62. Moreover, pharmacological or genetic blocking of autophagy enhanced salidroside -induced apoptosis, indicating the cytoprotective role of autophagy in salidroside-treated SW1353 cells. Salidroside also induced TFEB (Ser142) dephosphorylation, subsequently to activated TFEB nuclear translocation and increase of TFEB reporter activity, which contributed to lysosomal biogenesis and the expression of autophagy-related genes. Importantly, we found that salidroside triggered the generation of ROS in SW1353 cells. Furthermore, NAC, a ROS scavenger, abrogated the effects of salidroside on TFEB-dependent autophagy. CONCLUSIONS: These data demonstrate that salidroside increased TFEB-dependent autophagy by activating ROS signaling pathways in human chondrosarcoma cells. These data also suggest that blocking ROS-TFEB-dependent autophagy to enhance the activity of salidroside warrants further attention in treatment of human chondrosarcoma cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Condrossarcoma/tratamento farmacológico , Glucosídeos/farmacologia , Fenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Condrossarcoma/metabolismo , Glucosídeos/química , Humanos , Fenóis/química , Rhodiola/química , Transdução de Sinais/efeitos dos fármacos
11.
Ecotoxicology ; 30(7): 1287-1289, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34286412
12.
Arch Environ Contam Toxicol ; 71(3): 365-76, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27421725

RESUMO

As a systematic research at basin scale, this study explored the composition and concentration characteristics of 16 priority polycyclic aromatic hydrocarbons (PAHs) in sediments, water, and suspended particulate matter (SPM) in the water systems (rivers, lakes, and reservoirs) in the Hai River Basin through literature review. The sources and the ecosystem risks of PAHs in the sediments in the entire basin were specially discussed with diagnostic ration, PAHs composition, and an improved risk quotient method. Results showed that the total concentration of PAHs varied from 99.65 to 25,303 ng g(-1) dry weight in sediments, from 51.0 to 559.1 ng L(-1) in water, and from 4528 to 51,080 ng g(-1) dry weight in SPM, respectively. The dominant PAHs in the three examined phases were 2-3 rings in most waterbodies. PAHs in the rivers were from mixed sources (petrogenic and pyrolytic inputs), whereas those in lakes and reservoirs were mainly from biomass combustion and petroleum combustion. PAHs in the entire basin exhibited moderate to high ecological risk, and the rivers (especially Hai River, Jiyun River, Chaobai River, and Beiyun River) suffered higher ecological risk than reservoirs and lakes. Most of the rivers with higher PAHs risk flow through or around megacity Beijing and Tianjin.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , China , Medição de Risco , Poluição Química da Água/estatística & dados numéricos
13.
Ecotoxicology ; 24(5): 967-84, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25847103

RESUMO

Phthalate esters (PAEs) are widely used in the manufacturing of plastics, and the demand for PAEs has grown rapidly, especially in China. This trend will lead to much more environmental PAE contamination. PAEs are listed as priority substances in the European Union and are therefore subject to ecological risk assessments. This paper reviews the literature concerning the pollution status of PAEs and their ecological risk to aquatic environments. Risk quotients (RQs) based on the predicted no effect concentration and PAE concentrations in aquatic environments demonstrated significant (10 ≤ RQ < 100) or expected (RQ ≥ 100) potential adverse effects for algae, Daphnia, and fish in aquatic environments near PAE-based industrial and urban areas. Thus, the ecological risk of PAEs in Chinese aquatic environments should be considered, especially in areas where commercial plastics are produced.


Assuntos
Poluição Ambiental/análise , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Animais , China , Monitoramento Ambiental/métodos , Poluição Ambiental/efeitos adversos , Ácidos Ftálicos/toxicidade , Plastificantes/análise , Medição de Risco/métodos , Poluentes Químicos da Água/toxicidade
14.
Zhongguo Zhong Yao Za Zhi ; 40(4): 607-13, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-26137677

RESUMO

In this study, the growth and accumulation of active components of Salvia miltiorrhiza in twenty two experimental sites which crossing through three typical climate zones. The S. miltiorrhiza seedlings with the same genotype were planted in each site in spring, which were cultivated in fields with uniform management during their growing seasons till to harvest. The diterpene ketones (dihydrotanshinone, cryptotanshinone, tanshinone I and tanshinone II(A)) in S. miltiorrhiza root samples were determined by using high-performance liquid chromatography (HPLC) method. The biomass of root (root length, number of root branches, root width and dry weight) was also measured. The results showed that tanshinone II(A) in all samples of each site were higher than the standards required by China Pharmacopoeia. It has been found there is a relationship between root shape and climate change. The correlation analysis between active components and meteorological factors showed that the accumulation of tanshinones were effected by such meteorological factors as average relative humidity from April to October > average vapor pressure from April to October > average temperature difference day and night from April to October > annual average temperature and so on. The correlation analysis between root biomass and meteorological factors exhibited that root shape and accumulation of dry matter were affected by those factors, such as average annual aboveground (0-20 cm) temperature from April to October > annual average temperature > average vapor pressure from April to October > annual active accumulated temperature > annual average temperature > average vapor pressure from April to October. The accumulation of tanshinones and biomass was increased with the decrease of latitude. At the same time, the dry matter and diameter of root decreased if altitude rises. In addition, S. miltiorrhiza required sunlight is not sophisticated, when compared with humid and temperature. To sum up, S. miltiorrhiza can adapt to a variety of climatic conditions and the southern warm humid climate is more conducive to its growth and accumulation of active components.


Assuntos
Medicamentos de Ervas Chinesas/análise , Raízes de Plantas/crescimento & desenvolvimento , Salvia miltiorrhiza/química , Biomassa , China , Mudança Climática , Ecossistema , Raízes de Plantas/química , Salvia miltiorrhiza/crescimento & desenvolvimento , Temperatura
15.
Ecotoxicology ; 23(4): 553-66, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24488270

RESUMO

Heavy metals may adversely affect the structure and function of the periphyton community in lake ecosystems. We carried out samplings of three habitats at eight sites located in the Lake Baiyangdian that is strongly influenced by wastewater discharge (Sites 1 and 2), aquaculture and densely populated villages (Sites 3, 6, and 8), and the least disturbed (Sites 4, 5, and 7). Cu, Ni, Pb, Zn, Hg, Cd, and Cr were determined in these samples, and the periphyton community was simultaneously studied. The contamination factor (C f (i) ) was estimated for every metal as the ratio between pre-industrial records from sediments (C n (i) ) and present concentration values (C (i) ), and the individual potential risk (E r (i) ) was calculated by multiply the toxic response factor (Tr (i) ) and C f (i) for a given substance were based on Hakanson's methodology. The RI was obtained for each sampling site by summing the values of E r (i) first and the average was calculated across the sampling sites. The results showed that the RI for all three habitats was lower than 94, and they are in decreasing order: wastewater discharge, aquaculture and densely populated villages, and the least anthropogenic impacted. When the three sampling seasons were compared, August appeared to show the highest risk, followed by April and November. The RI values showed negative correlations (r = -0.444 to -0.851, p < 0.05) with the structural and functional metrics. The best correlation was detected between chlorophyll c/chlorophyll a (Chl c/a) ratio and E r (i) Hg (r = -0.851, p < 0.01). Our results suggest the periphyton community can be used in bio-monitoring.


Assuntos
Monitoramento Ambiental , Metais/toxicidade , Microbiologia da Água , Poluentes Químicos da Água/toxicidade , China , Lagos , Metais/análise , Plantas , Medição de Risco , Poluentes Químicos da Água/análise , Qualidade da Água
16.
Ecotoxicology ; 23(4): 495-505, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24557602

RESUMO

The variations and associations of abiotic and biotic variables in Baiyangdian Lake, China, were analyzed in situ. Abiotic variables included eleven water quality parameters, and were characterized by water quality index (WQI). Biotic variables included periphyton function and diversity metrics. WQI differed in different seasons at sampling sites and the highest value of WQI was observed in October 2009. Periphyton function metrics, expressed by extracellular enzyme activities of alkaline phosphatase, ß-glucosidase and leucine aminopeptidase, gross primary productivity and daily respiration rate, and diversity indices, in terms of Shannon diversity index and Berger-Parker abundance index, showed significantly temporal and spatial variations. Regression linear analysis illustrated a fairly good correlation of WQI with periphyton function and diversity indices, Shannon diversity index was the best correlated with WQI (r = 0.904, P < 0.01), followed by leucine aminopeptidase (r = -0.847, P < 0.01) and Berger-Parker abundance index (r = -0.840, P < 0.01), alkaline phosphatase, ß-glucosidase and gross primary productivity also showed a good inverse correlation with WQI. Redundancy analysis suggested that eleven environmental variables explained a significant amount of the variation in the periphyton community data. The study was helpful for us to understand chemical and ecological status of water quality, and give us messages for monitoring water quality accurately.


Assuntos
Biodiversidade , Lagos/microbiologia , Microbiologia da Água , Qualidade da Água , China , Lagos/química
17.
Ecotoxicology ; 23(4): 506-17, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24648030

RESUMO

The Haihe River Basin is a semiarid water resources area of China. River ecosystem was degraded for high population density and intensive water resources development activities. To assist in the improvement of the ecological integrity of this river ecosystem, an environmental flow assessment model was developed that consider both spatial structure and dominant eco-function parameters. River ecosystem was divided into three sub-ecosystems which including river reach, wetland and estuary based on the spatial structure of river ecosystem. River reach was divided into three types which including habitat restoration type (HR), water quality restoration type (WQR) and vegetation restoration substitute water quantity restoration type (VRSWQR) according to their dominant eco-function. The spatio-temporal distribution of environmental flow (EF) for the river ecosystem in the Haihe River Basin was assessed based on the model. The results indicate that the EF for the river reach, wetland, and estuary are 2.267, 1.532, and 0.972 billion m(3), respectively. The EF for HR type of river reach, the WQR type of river reach and VRSWQR type of river reach are 1.140, 1.138, and 0.154 billion m(3), which are equal to 4.320, 4.312, and 0.584 % of the average annual flow of 26.39 billion m(3), respectively. EF for river ecosystem in wet period (June-September), normal period (October-January) and dry period (February-May) are 2.999, 0.951, and 0.821 billion m(3), respectively. Annual EF for river ecosystem of the Basin are 4.771 billion m(3), which accounts for 18 % of the average annual flows of 26.39 billion m(3).


Assuntos
Estuários , Modelos Teóricos , Rios , Movimentos da Água , Áreas Alagadas , China
18.
Water Sci Technol ; 70(10): 1648-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25429453

RESUMO

It is essential to evaluate the ecological risk for the estuary cities area for the environmental restoration of the estuary. The ecological risk of six city areas from the Pearl River Estuary were evaluated by using the relative risk model. The relative risk assessment method was developed by considering the river network density in the sub-region. The results indicated that Dongguan had the largest ecological risk pressure with total risk scores as high as 10,846.3, and Hong Kong had the lowest ecological risk pressure with total risk scores up to 4,104.6. The greatest source was domestic sewage with total risk scores as high as 1,798.6, followed by urbanization and industry. Oxygen-consuming organic pollutants, organic toxic pollutants and nutrients were the major stressors of the water environment. In terms of habitats, the water environment was enduring the greatest pressure. For the endpoints, water deterioration faced the largest risk pressure.


Assuntos
Monitoramento Ambiental , Estuários , Poluentes Químicos da Água/análise , China , Cidades , Meio Ambiente , Hong Kong , Indústrias , Modelos Teóricos , Medição de Risco , Esgotos , Urbanização
19.
Small Methods ; 8(1): e2300728, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37806769

RESUMO

Sb2 Se3 solar cells deposited by rapid thermal evaporation (RTE) have drawn extensive attention owing to their compatibility with the commercial production line of CdTe solar cells and can be used to fabricate high-quality Sb2 Se3 films with high reproducibility. However, the deposition pressure during the RTE process has not been clearly explored, although it has a significant effect on the Sb2 Se3 film quality. A novel two-step deposition strategy is proposed that finely regulates the deposition pressure to improve the quality of Sb2 Se3 absorber layers, thereby improving the device performance of Sb2 Se3 solar cells. This novel method includes a rapid deposition process under a low pressure (5 mTorr) and an in situ annealing process under a relatively high pressure (200 Torr). The maximum power conversion efficiency (PCE) of Sb2 Se3 solar cells fabricated by two-step deposited approach is up to 8.12%. The PCE enhancement is attributed to the increased grain size, reduced grain boundaries, modified surface Fermi level gradient of the absorber layer, and improved defect performance. This innovative deposition technique is expected to benefit other low-melting-point metal sulfoselenides for solar cell applications.

20.
Phys Chem Chem Phys ; 15(24): 9775-82, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23674049

RESUMO

In this paper, we report the porosity and heterojunction effects of hematite (α-Fe2O3) on the photoelectrochemical (PEC) water splitting properties. The worm-like mesoporous hematite thin films (MHFs) with a pore size of ~9 nm and a wall thickness of ~5 nm were successfully obtained through the self-assembly process. MHFs formed on FTO showed much better PEC properties than those of nonporous hematite thin films (NP-HF) owing to the suppression of charge recombination. The PEC data of MHFs under front and back illumination conditions indicated that the porous structure allows the diffusion of electrolyte deep inside the MHF increasing the number of holes to be utilized in the water oxidation reaction. A heterojunction structure was formed by introducing a thin layer of SnO2 (~15 nm in thickness) between the MHF and FTO for a dramatically enhanced PEC response, which is attributed to the efficient electron transfer. Our spectroscopic and electrochemical data show that the SnO2 layer functions as an efficient electron transmitter, but does not affect the recombination kinetics of MHFs.

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