Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Small ; : e2401797, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38577831

ABSTRACT

The interfacial 2D/3D perovskite heterostructures have attracted extensive attention due to their unique ability to combine the high stability of 2D perovskites with the remarkable efficiency of 3D perovskites. However, the carrier transport mechanism within the 2D/3D perovskite heterostructures remains unclear. In this study, the carrier transport dynamics in 2D/3D perovskite heterostructures through a variety of time-resolved spectroscopic measurements is systematically investigated. Time-resolved photoluminescence results reveal nanosecond hole transfer from the 3D to 2D perovskites, with enhanced efficiency through the introduction of fluorine atoms on the phenethylammonium (PEA) cation. Transient absorption measurements unveil the ultrafast picosecond electron and energy transfer from 2D to 3D perovskites. Furthermore, it is demonstrated that the positioning of fluorination on the PEA cations effectively regulates the efficiency of charge and energy transfer within the heterostructures. These insightful findings shed light on the underlying carrier transport mechanism and underscore the critical role of cation fluorination in optimizing carrier transport within 2D/3D perovskite heterostructure-based devices.

2.
Heliyon ; 9(2): e13280, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36816311

ABSTRACT

Environmental and urban sciences have shown that brownfield problems significantly impact human behavior and the environment. Understanding the sustainable planning and redevelopment of brownfields can help governments and financial partners consider sustainable urban policies a key priority. This study presents a bibliometric analysis of research publications on the sustainable redevelopment of brownfields through the Scopus database since 1990. The redevelopment of brownfields has an essential role in urban sustainability, so research trends on the sustainable redevelopment of brownfields in previous literature are revealed. To our knowledge, the bibliometric analysis of the term sustainable redevelopment of brownfields is not yet an accentuated field of research. To do this, this study aims to fill this gap by offering a broad overview of the bibliometric analysis of the literature relating to this term. Brownfield and contaminated land are used as keywords in the article titles taken from the Scopus database on September 07, 2021. A total of 7197 scientific articles (Scopus) were reviewed to show how the research on "brownfields or contaminated land" has emerged and developed. Social media analysis (VOSviewer) was used for data visualization, and Harzing's Publish or Perish used for metrics and citation analysis. The results showed an increase in the growth rate of the literature on sustainable brownfield redevelopment since 1990, particularly from 2011 to 2020. Research related to the sustainable redevelopment of brownfields has involved various authors and is published in various languages. There are 160 authors from 126 countries and 160 institutions. China is the largest contributor to this study, followed by the United States and the United Kingdom. The Chemosphere Journal has published the most articles on the sustainable redevelopment of brownfields. Although our results also indicate that studies on the sustainable redevelopment of brownfields are mainly carried out in the field of environmental sciences. Some avenues for future research have been analyzed in three directions so that sustainable development can easily be integrated into a brownfield redevelopment project.

3.
MedComm (2020) ; 4(1): e206, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36699286

ABSTRACT

Tetrandrine (TET) has been used to treat silicosis in China for decades. The aim of this study was to facilitate rational repurposing of TET against SARS-CoV-2 infection. In this study, we confirmed that TET exhibited antiviral potency against SARS-CoV-2 in the African green monkey kidney (Vero E6), human hepatocarcinoma (Huh7), and human lung adenocarcinoma epithelial (Calu-3) cell lines. TET functioned during the early-entry stage of SARS-CoV-2 and impeded intracellular trafficking of the virus from early endosomes to endolysosomes. An in vivo study that used adenovirus (AdV) 5-human angiotensin-converting enzyme 2 (hACE2)-transduced mice showed that although TET did not reduce pulmonary viral load, it significantly alleviated pathological damage in SARS-CoV-2-infected murine lungs. The systemic preclinical pharmacokinetics were investigated based on in vivo and in vitro models, and the route-dependent biodistribution of TET was explored. TET had a large volume of distribution, which contributed to its high tissue accumulation. Inhaled administration helped TET target the lung and reduced its exposure to other tissues, which mitigated its off-target toxicity. Based on the available human pharmacokinetic data, it appeared feasible to achieve an unbound TET 90% maximal effective concentration (EC90) in human lungs. This study provides insights into the route-dependent pulmonary biodistribution of TET associated with its efficacy.

4.
Article in English | MEDLINE | ID: mdl-35565010

ABSTRACT

For current territory development planning in China, city center accessibility (CCA) has gained increasing attention for evaluating the expansion of urban areas. How should CCA and its differences between the automobile and public transit (PT) modes be measured? We analyzed CCA from travel time and travel cost perspectives using the travel data obtained from the Baidu Map at a 100 m × 100 m resolution. The GWR was then examined to explore the correlation between the explanatory variables and the CCA differences. Automobile-based CCA shows a concentric structure and varies with time, while PT-based CCA has an apparent linear expansion along the metro lines and fluctuates less. When measuring by travel cost instead of travel time, CCA gaps between the two modes are lessened, and the automobile's advantage is no longer evident. The distance from the metro stations has a significant positive effect on CCA differences, and the positive effect concentrates in the 3.6 km range (measured by travel time) and 2.8 km range (measured by travel cost) around the metro stations. Our study highlights the importance of multiple perspectives when comparing the accessibility of different transport modes, and the results also provide implications for policy-makers.


Subject(s)
Automobiles , Transportation , China , Cities , Travel
5.
J Environ Manage ; 313: 114976, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35367678

ABSTRACT

Building height, building density, and floor area ratio are the three key parameters in urban planning. However, little is known about their impact on indoor thermal environments as compared with outdoor thermal environments. The study aimed to investigate their impact on indoor air temperatures in Singapore. Singapore's residential buildings were reviewed from the perspective of the three parameters, and the Envi-met model was employed for simulation after its accuracy was confirmed by field experiments. Indoor air temperatures under 18 scenarios were simulated and analyzed. The analytical results revealed that among the three parameters, the building density was the most influential. An increase in building density reduced the indoor temperature. In Singapore, the building density increases from 0.0625 to 0.766, which reduced the mean indoor temperature by 4.7 °C. The indoor temperature decreased slightly with an increase in building height. An increase in building height from 12 to 72 m produced an indoor temperature decrease of approximately 1.7 °C. The influence of floor area ratio on indoor air temperature was the most complex. For a fixed floor area ratio of 2, the indoor temperature first increased and then decreased with an increase in building density, which resulted in an indoor temperature difference of 2.1 °C when the building density increased from 0.141 to 0.766.


Subject(s)
Air Pollution, Indoor , Air Pollution, Indoor/analysis , Singapore , Temperature
6.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3270-3287, 2021 Jul.
Article in Chinese | MEDLINE | ID: mdl-34396746

ABSTRACT

The multi-component pharmacokinetic study of Chinese herbal extracts elaborates the in vivo processes,including absorption,distribution,metabolism,and excretion,of multiple bioactive components,which is of significance in revealing pharmacodynamic material basis of Chinese herbal medicine. In recent years,with the innovation in ideas,and development of techniques and methods on traditional Chinese medicine( TCM) research,the pharmacokinetic studies of Chinese herbal extracts were extensively performed,and notable progress has been made. This paper reviewed the advancement of multi-component pharmacokinetics of Chinese herbal extracts in recent five years from analysis technology of biological sample,the pharmacokinetic characteristics of Chinese herbal medicine with complex system,and the impacts of processing and pathological state on pharmacokinetics of Chinese herbal extracts,aiming to provide a reference for quality control,product development and rational medication of Chinese herbal extracts.


Subject(s)
Drugs, Chinese Herbal , China , Humans , Medicine, Chinese Traditional , Quality Control
7.
Article in English | MEDLINE | ID: mdl-34444161

ABSTRACT

The window-to-wall ratio (WWR) significantly affects the indoor thermal environment, causing changes in buildings' energy demands. This research couples the "Envi-met" model and the "TRNSYS" model to predict the impact of the window-to-wall ratio on indoor cooling energy demands in south Hunan. With the coupled model, "Envi-met + TRNSYS", fixed meteorological parameters around the exterior walls are replaced by varied data provided by Envi-met. This makes TRNSYS predictions more accurate. Six window-to-wall ratios are considered in this research, and in each scenario, the electricity demand for cooling is predicted using "Envi-met + TRNSYS". Based on the classification of thermal perception in south Hunan, the TRNSYS predictions of the electricity demand start with 30 °C as the threshold of refrigeration. The analytical results reveal that in a 6-storey residential building with 24 households, in order to maintain the air temperature below 30 °C, the electricity required for cooling buildings with 0% WWR, 20% WWR, 40% WWR, 60% WWR, 80% WWR, and 100% WWR are respectively 0 KW·h, 19.6 KW·h, 133.7 KW·h, 273.1 KW·h, 374.5 KW·h, and 461.9 KW·h. This method considers the influence of microclimate on the exterior wall and improves the accuracy of TRNSYS in predicting the energy demand for indoor cooling.


Subject(s)
Cold Temperature , Microclimate , Meteorology , Seasons , Temperature
8.
Pharm Biol ; 59(1): 769-777, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34152236

ABSTRACT

CONTEXT: Total Glucosides of Paeony (TGP) capsule possesses various hepatoprotective activities. No study is available concerning TGP's concentration-effect relationship on hepatoprotection. OBJECTIVE: To establish a pharmacokinetics-pharmacodynamics (PK-PD) modelling on TGP capsule's hepatoprotection after a single oral administration in hepatic injury rats. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into five groups (n = 6): control, model (hepatic injury), treated-H (2.82 g/kg), treated-M (1.41 g/kg), and treated-L (0.705 g/kg) groups. All treated groups rats were intragastrically administered a single dose. An LC-MS/MS method was applied to determine paeoniflorin (Pae) and albiflorin (Alb) in rat serum. The effects of single-dose TGP on serum alanine transaminase (ALT), aspartate transaminase (AST) and total bile acid (TBA) were evaluated in hepatic injury rats. RESULTS: Single dose (2.82, 1.41, or 0.705 g/kg) TGP capsule could real-time down-regulate serum TBA but not ALT and AST in hepatic injury rats within 20 h. An inhibitory effect Sigmoid Emax of PK-PD modelling was established using Pae and Alb as PK markers and serum TBA as effect index. Pharmacodynamic parameters were calculated. For treated-H, treated-M and treated-L group, respectively, E0 were 158.1, 226.9 and 245.4 µmol/L for Pae, 146.1, 92.9 and 138.4 µmol/L for Alb, Emax were 53.0, 66.0, and 97.1 µmol/L for Pae, 117.4, 249.7 and 60.0 µmol/L for Alb, and EC50 were 9.3, 5.2 and 2.7 µg/mL for Pae, 2.3, 0.8, and 0.8 µg/mL for Alb. DISCUSSION AND CONCLUSIONS: Serum TBA is a sensitive effect index for TGP's single dose PK-PD modelling, and it is potential for further multi-dose studies of TGP' effect on hepatic injury. The study provides valuable information for TGP's mechanistic research and rational clinical application.


Subject(s)
Bile Acids and Salts/blood , Chemical and Drug Induced Liver Injury/blood , Drugs, Chinese Herbal/pharmacokinetics , Glucosides/pharmacokinetics , Paeonia , Animals , Bile Acids and Salts/antagonists & inhibitors , Carbon Tetrachloride/toxicity , Chemical and Drug Induced Liver Injury/drug therapy , Drugs, Chinese Herbal/administration & dosage , Glucosides/administration & dosage , Male , Rats , Rats, Sprague-Dawley , Tandem Mass Spectrometry/methods
9.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1752-1762, 2021 Apr.
Article in Chinese | MEDLINE | ID: mdl-33982479

ABSTRACT

Traditional Chinese medicine(TCM) injections boast a definite efficacy and have been widely used in clinic. However, the problems in medication safety have been attracted increasing attention. Pharmacokinetics is of significance to guiding TCM injection administration regimen design and improving safety and effectiveness in clinical use. In recent years, with the improvement of ideas, technology and methods of TCM studies, the pharmacokinetic studies of TCM injections have been broadly performed, with a notable progress. This paper reviewed the advance in pharmacokinetics studies of TCM injections in recent ten years, which mainly focused on pre-clinical concentration-time course, distribution, metabolism and excretion in vivo based on analysis techniques, pharmacokinetic interactions of constitutes, impact of pathological state, pharmacokinetic interactions between TCM injection and chemical drugs, and clinical pharmacokinetics studies of TCM injections, in the expectation of providing reference for studies on quality control, product development and rational clinical use of TCM injections.


Subject(s)
Drugs, Chinese Herbal , Medicine, Chinese Traditional , Injections , Quality Control
10.
Ecotoxicol Environ Saf ; 156: 125-134, 2018 Jul 30.
Article in English | MEDLINE | ID: mdl-29549735

ABSTRACT

A significant amount of antimony (Sb) enters into the environment every year because of the wide use of Sb compounds in industry and agriculture. The exposure to Sb, either direct consumption of Sb or indirectly, may be fatal to the human health because both antimony and antimonide are toxic. Firstly, the introduction of Sb chemistry, distribution and health threats are presented in this review, which is essential to the removal techniques. Then, we provide the recent and common techniques to remove Sb, including adsorption, coagulation/flocculation, membrane separation, electrochemical methods, ion exchange and extraction. Removal techniques concentrate on the advantages, drawbacks, economical efficiency and the recent achievements of each technique. We also take an overall consideration of experimental conditions, comparison criteria, and economic aspects.


Subject(s)
Antimony/isolation & purification , Public Health , Animals , Environmental Monitoring , Food Chain , Food Contamination/analysis , Groundwater/chemistry , Humans , Soil/chemistry , Soil Pollutants/isolation & purification , Vegetables/chemistry , Water Pollutants, Chemical/isolation & purification
11.
Carbohydr Polym ; 157: 576-585, 2017 Feb 10.
Article in English | MEDLINE | ID: mdl-27987965

ABSTRACT

Fe3O4@SiO2-Chitosan/GO (MSCG) nanocomposite was investigated by various techniques (SEM, TEM, XRD, VSM, FT-IR, XPS) for the removal of tetracycline (TC). Effects of pH, zeta potential and initial contaminant concentration were studied in detail. Four background cations (Na+, K+, Ca2+ and Mg2+) with a concentration of 0.01M showed little influence on the TC adsorption at the studied pH range while the divalent heavy metal cation Cu(II) could significantly enhance the adsorption. The results indicated that the highest adsorption capacity of TC were 183.47mmol/kg and 67.57mmol/kg on MSCG with and without Cu(II), respectively. According to mechanism investigation for the adsorption of TC by pH impact study and XPS analysis, besides electrostatic interaction and π-π interactions, the Cu(II) also acts as a bridge between TC and MSCG, which significantly improve the adsorption of TC. This study provided valuable guidance and effective method for the removal of TC from aquatic environments.


Subject(s)
Chitosan , Copper/chemistry , Graphite , Nanocomposites , Tetracycline/isolation & purification , Adsorption , Ions , Oxides , Silicon Dioxide , Spectroscopy, Fourier Transform Infrared
12.
Environ Sci Pollut Res Int ; 23(23): 23606-23618, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27614648

ABSTRACT

In this work, a novel potential adsorbent, citric acid (CA)-modified biochar, named as CAWB, was obtained from water hyacinth biomass by slow pyrolysis in a N2 environment at 300 °C. The CA modification focused on enhancing the contaminants adsorption capacity of biochar pyrolyzed at relatively low temperature. Over 90 % of the total methylene blue (MB) could be removed at the first 60 min by CAWB, and the maximum MB adsorption capacity could reach to 395 mg g-1. The physicochemical properties of CAWB was examined by FTIR, XPS, SEM, and BET analysis. The results indicated that the additional carboxyl groups were introduced to the surface of CAWB via the esterification reaction with CA, which played a significant role in the adsorption of MB. Batch adsorption studies showed that the initial MB concentration, solution pH, background ionic strength, and temperature could affect the removal efficiency obviously. The adsorption process could be well described by the pseudo-second-order kinetic model and Langmuir isotherm. Thermodynamic analysis revealed that the MB adsorption onto CAWB was an endothermic and spontaneous process. The regeneration study revealed that CAWB still exhibited an excellent regeneration and adsorption performance after multiple cycle adsorptions. The adsorption experiments of actual dye wastewater by CAWB suggested that it had a great potential in environmental application.


Subject(s)
Charcoal/chemistry , Citric Acid/chemistry , Eichhornia/chemistry , Methylene Blue/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Biomass , Hydrogen-Ion Concentration , Kinetics , Methylene Blue/isolation & purification , Temperature , Wastewater/chemistry , Water Pollutants, Chemical/isolation & purification
13.
Environ Sci Pollut Res Int ; 23(10): 10189-99, 2016 May.
Article in English | MEDLINE | ID: mdl-26875820

ABSTRACT

Heavy metal pollution is a major concern of the public due to their threats to the safety of food chains. A 60-day pot experiment was conducted using Macleaya cordata as plant material to investigate the phytoremediation potential and anti-oxidative responses of M. cordata under different Cd stress. Significant growth inhibition phenomenon and toxic symptoms were not detected in the experiment. The high biomass of the plant provided high accumulation capacity for Cd with an average dry weight of 3.6 g. The maximum extraction amount of Cd was 393 µg·plant(-1), suggesting that this species had potential for phytoremediation of Cd-contaminated soil. A slight increase of chlorophyll (CHL) content was observed in Cd10 treatment. The plant was confirmed to have relatively high tolerance to the Cd stress on the basis of tolerance indexes (TI), relative water content, and CHLa/CHLb ratio. M. cordata could maintain high level of superoxide dismutase (SOD) activity under Cd stress, indicating strong tolerance capacity for reactive oxygen species (ROS) in plant cells. Catalase (CAT) activity show a certain range of decline in the experiment compare to the control. And peroxidase (POD) activity in leaves changed irregularly when compared to the control. The malondialdehyde (MDA) content increased as Cd concentration elevated compared to the control. In addition, as an inedible crop with relatively high economic value, M. cordata have shown the advantage of high biomass and high tolerance under Cd stress, which can provide a new plant resource for sustainable phytoremediation.


Subject(s)
Biodegradation, Environmental , Cadmium/metabolism , Papaveraceae/metabolism , Soil Pollutants/metabolism , Biomass , Chlorophyll/metabolism , Malondialdehyde/metabolism , Plant Cells/metabolism , Plant Leaves/metabolism , Plant Roots/metabolism , Soil
14.
Environ Sci Pollut Res Int ; 22(13): 9999-10008, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25666476

ABSTRACT

Hydroponic experiments were performed to investigate the ameliorating effects and mitigation mechanisms of selenium and silicon on Cd toxicity in Boehmeria nivea (L.) Gaud. Metal accumulation, chlorophyll content, activities of antioxidant enzymes, and antioxidant contents in ramie were evaluated. The results revealed that cadmium was mainly accumulated in the roots of plants rather than in the aerial parts. Additionally, under 5 mg L(-1) Cd stress, both Se (1 µmol L(-1)) and Si (1 mmol L(-1)) treatments decreased the Cd concentrations in plants. Besides, the treatments also inhibited the translocation ability of Cd from roots to the aboveground parts, which might be related to the decline of generation of reactive oxygen species (ROS). The application of Se and/or Si ameliorated Cd toxicity via stimulating the activities of antioxidant enzymes such as superoxide dismutase (SOD), guaiacol peroxidase (POD), and ascorbate peroxidase (APX), which resulted in the significant decrease of the contents of malondialdialdehyde (MDA) and hydrogen peroxide (H2O2) in ramie leaves. In addition, the content of nonenzymatic antioxidant such as glutathione (GSH) was increased significantly through the addition of selenite and silicate. Also, ascorbate (AsA) and vitamin E played a crucial role in scavenging excess ROS within plants. On the whole, appropriate doses of Se and Si were found to benefit plant growth and enhance the ability of ramie to alleviate Cd-induced stress. Moerover, the effects of combination of Se and Si appeared to be more superior compared to addition separately in response to Cd stress.


Subject(s)
Boehmeria/physiology , Cadmium/toxicity , Selenium/chemistry , Silicon/chemistry , Soil Pollutants/toxicity , Ascorbate Peroxidases/metabolism , Ascorbic Acid/metabolism , Chlorophyll/metabolism , Glutathione/metabolism , Hydrogen Peroxide , Oxidative Stress/radiation effects , Peroxidase , Plant Leaves/metabolism , Plant Roots/drug effects , Reactive Oxygen Species/pharmacology , Superoxide Dismutase/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...