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1.
Sci Total Environ ; 942: 173784, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38851330

ABSTRACT

Forest foundation species, vital for shaping community structure and dynamics through non-trophic level interactions, are key to forest succession and sustainability. Despite their ecological importance, the habitat ranges of these species in China and their responses to future climate change remain unclear. Our study employed the optimal MaxEnt model to assess the range shifts and their essential drivers of four typical forest foundation species from three climatic zones in China under climate scenarios, including Acer tegmentosum, Acer pseudo-sieboldianum (temperate zone), Quercus glandulifera (subtropical zone), and Ficus hispida (tropical zone). The optimal MaxEnt model exhibited high evaluation indices (AUC values > 0.90) for the four foundation species, indicating excellent predictive performance. Currently, we observed that A. tegmentosum and A. pseudo-sieboldianum are predominantly inhabited temperate forest areas in northeastern China, Q. glandulifera is primarily concentrated in subtropical forests in southeastern China, and F. hispida is mainly distributed across the tropical forests in southern China. Climate factors, particularly temperature, emerged as the primary environmental factors influencing the potential range of forest foundation species. Moreover, precipitation strongly influenced the potential range of A. tegmentosum and A. pseudo-sieboldianum, while elevation exhibited a greater impact on the range of Q. glandulifera and F. hispida. Under future climate scenarios, suitable areas for A. tegmentosum and A. pseudo-sieboldianum tend to expand southward, F. hispida tends to expand northward, while Q. glandulifera exhibited a tendency to contract towards the center. This study advances our understanding of the spatial and temporal dynamics of forest foundation species in China under climate change, providing critical insights for conservation efforts and sustainable forest management practices.


Subject(s)
Climate Change , Forests , Quercus , China , Acer , Ecosystem , Ficus , Trees
2.
RSC Adv ; 13(31): 21643-21654, 2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37476034

ABSTRACT

In this work, we present a binary composite of La(OH)3@Ni(OH)2 on carboxyl graphene (La@Ni/CG) as an electrode material. The layered La@Ni/CG double hydroxides (LDHs) were synthesized by a simple electrodeposition method in which La(OH)3 nanoparticles were first adsorbed onto carboxyl graphene and then coated with Ni(OH)2, with different particle shapes due to the large pH change near the cathodic region. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) were used to characterise the as-prepared La@Ni/CG composite. These results showed that the La@Ni/CG composite exhibited improved electrochemical properties, including large specific capacitance (1334.7 F g-1 at 1.4 A g-1) and capacity retention of 90.6% even after 3000 cycles, and excellent rate capability. The improved electrochemical performance of the composite can be attributed to the synergistic effect of surface adsorption and conductive pathways provided by the multiple active species (Ni, La and C) in the La@Ni/CG composite. The results presented in this work provide advances in the efficient design of nanomaterial based electrochemical energy storage devices.

3.
ACS Omega ; 6(8): 5399-5407, 2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33681579

ABSTRACT

Lanthanum-based materials have attained increasing attention because of their high adsorption property of phosphate ions and their environmental harmlessness. However, challenges still remain to improve the phosphate adsorption capacity and find suitable materials for the lanthanum attachment substrate. Nickel foam with characteristics such as excellent uniformity, large specific surface area, high porosity, and low conductivity is considered to be the alternative for the preparation of lanthanum-based adsorption materials. An efficient adsorbent foamed nickel-based La (OH)3 nanowire was first prepared with a facile one-step electrodeposition method. The batch static adsorption tests of simulative wastewater (e.g., coexisting ions and solution pH values) were employed to investigate the phosphate adsorption kinetics and solution matrix effects of the materials. The results indicate that the composite exhibits fast adsorption kinetics within 30 min and high selectivity to phosphate under interference from competing ions. The pH value of wastewater has great influence on the absorption of phosphate, and optimal adsorption capacity can be achieved over a pH 4-6 range. Various findings revealed that the adsorption behavior of lanthanum hydroxide/foamed nickel [La(OH)3/Ni] followed inner-sphere adsorption through the ligand-exchange mechanism. The prepared material is expected to be an enormous potential candidate for the removal of low-concentration phosphorus from effluents.

4.
RSC Adv ; 11(62): 39399-39411, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-35492442

ABSTRACT

Carbon materials have been used as negative electrodes for supercapacitor applications; nevertheless, owing to the low capacitance, they have limited ability to enhance the supercapacitor electrochemical properties. Here, we employ a facile chemical precipitation method for preparing a squirrel cage structure Fe3O4@carbon nanocomposite. In this architecture, the carbonized crosslinked bovine serum albumin (C) will play critical roles, serving as a skeleton for the deposition of Fe3O4 and a transportation pathway like "high-speed rail" for electrons, maintaining the structural stability as well as accommodating the volume expansion of Fe3O4 and facilitating electron transportation and the electrolyte ion diffusion. The iron oxide nanoparticles (Fe3O4) exhibit superior reversible redox characteristics, hence increasing the supercapacitor performance. Benefiting from a stable structure, an aqueous asymmetric supercapacitor using a CNT@Ni(OH)2 positive electrode (cathode) and Fe3O4@C negative electrode (anode) has also been assembled, which presents a high energy density of 17.3 W h kg-1 at a power density of 700 W kg-1. The strategy for choice of Fe3O4@C composites will provide new opportunities for future supercapacitors with superior cyclability and high power density.

5.
ACS Omega ; 5(9): 4532-4541, 2020 Mar 10.
Article in English | MEDLINE | ID: mdl-32175499

ABSTRACT

Crystalline iron oxides/hydroxides are generally preferred as supercapacitor electrode materials instead of the low-crystalline structure, despite the fact that an amorphous phase could have a comprehensive electrochemical performance owing to its structural disorder. Herein, we present a facile and scalable method for preparing amorphous FeOOH nanoflowers@multi-walled carbon nanotubes (FeOOH NFs@MWCNTs) composites. The resulting hybrid nanoflowers hold a distinctive heterostructure composed of a self-assembled amorphous FeOOH nanofilm on the MWCNTs surface. The low-crystalline 1FeOOH NFs@1MWCNTs composites at pH 8 exhibit a high comprehensive capacitive performance, which may be attributed to the advantageous structural features. In a -0.85 to 0 V vs Ag/AgCl potential window, the prepared hybrid electrode delivers a high specific capacitance of 345 F g-1 at a current density of 1 A g-1, good cycling stability (76.4% capacity retention over 5000 consecutive cycles), and outstanding rate performance (167 F g-1 at 11.4 A g-1). This work may trigger the possibilities of these nanomaterials for further application in supercapacitor electrodes, specifically low-crystalline oxide/hydroxide-based electrode materials.

6.
Zhong Yao Cai ; 38(4): 766-9, 2015 Apr.
Article in Chinese | MEDLINE | ID: mdl-26672345

ABSTRACT

OBJECTIVE: To establish the quality control and evaluation methods of Panax notoginseng on promoting blood circulation and removing blood stasis effects, by determining cell index to evaluate the quality of Panax notoginseng from different habitats. METHODS: Using the real-time cell electronic analysis technology (RTCA) to examine the biological activity of specific cell-dependent cell lines on Panax notoginseng extracts. Changing trends and laws of the samples within a certain time were analyzed, and the cell index at the optimum time was determined. RESULTS: In four batches of Panax notoginseng from different habitats, cell index of Panax notoginseng from Chuxiong of Yunnan Province at the optimal time of 38 h was the highest, and the biological activity was the strongest. Cell index of Panax notoginseng from Wenshan of Yunnan Province at the optimal time of 38 h cells was the lowest, and the biological activity was the weakest. CONCLUSION: The method based on the real-time cell electronic analysis technology can initially be used in the detection of biological activity of Panax notoginseng.


Subject(s)
Drugs, Chinese Herbal/standards , Panax notoginseng , China , Electronics , Humans , Quality Control
7.
Zhongguo Zhong Yao Za Zhi ; 40(2): 231-5, 2015 Jan.
Article in Chinese | MEDLINE | ID: mdl-26080550

ABSTRACT

The objective of the present study was to establish a method based on principal component analysis (PCA) for the study of transdermal delivery of Chinese medicinal formulae, and to choose the best penetration enhancers for Qingfei Xiaocuo gel depend on this method. Using improved Franz type diffusion cell and excised rat skin in vitro as transdermal barrier, the receptive solution fingerprint was established by HPLC, harvesting the areas of the common peaks in the fingerprint, then the total factor scores of the concentrations at different times were calculated using PCA and were employed instead of the concentrations to compute the cumulative amounts (Q12) and enhancement ratio (ER), the latter of which were considered as the indexes for optimizing penetration enhancers. Compare to the control group, the ER of the other groups increased significantly and furthermore, 2.5% azone with 2.5% menthol manifested the best effect. PCA represent most information in the receptive solution, the method above could choose the best penetration enhancers, it could be a reference for the study of transdermal delivery of Chinese medicinal formulae.


Subject(s)
Drugs, Chinese Herbal/pharmacokinetics , Medicine, Chinese Traditional , Principal Component Analysis , Skin/metabolism , Administration, Cutaneous , Animals , Drugs, Chinese Herbal/analysis , Gels , In Vitro Techniques , Male , Mice
8.
Article in English | MEDLINE | ID: mdl-24922600

ABSTRACT

Solasodine is a poisonous alkaloid chemical compound that occurs in plants of the Solanaceae family. A simple and selective liquid chromatography mass spectrometry method for determination of solasodine in rat plasma was developed and validated over the range of 3-1,000 ng/mL. Chromatographic separation was achieved on a C18 (2.1 mm×50 mm, 3.5 µm) column with acetonitrile-0.1% formic acid in water as mobile phase with gradient elution. The flow rate was set at 0.4 mL/min. After addition of midazolam as internal standard (IS), liquid-liquid extraction by ethyl acetate was used as sample preparation. An electrospray ionization source was applied and operated in positive ion mode; selective ion monitoring mode was used for quantification with target ions m/z 414 for solasodine and m/z 326 for IS. Mean recoveries of solasodine in rat plasma were in the range of 87.6-94.1%. Matrix effects for solasodine were between 94.9% and 102.3%. Coefficient of variation of intra-day and inter-day precision were both <13%. The accuracy of the method ranged from 94.4% to 105.3%. The method was successfully applied to a pharmacokinetic study of solasodine after oral administration of 20mg/kg in rats.


Subject(s)
Chromatography, Liquid/methods , Solanaceous Alkaloids/blood , Spectrometry, Mass, Electrospray Ionization/methods , Administration, Oral , Animals , Limit of Detection , Male , Rats, Sprague-Dawley , Solanaceous Alkaloids/administration & dosage
9.
Ying Yong Sheng Tai Xue Bao ; 25(9): 2477-85, 2014 Sep.
Article in Chinese | MEDLINE | ID: mdl-25757295

ABSTRACT

Altitudinal patterns of species richness and species range size and their underlying mechanisms have long been a key topic in biogeography and biodiversity research. Rapoport's rule stated that the species richness gradually declined with the increasing altitude, while the species ranges became larger. Using altitude-distribution database from Xiaolongshan Reverse, this study explored the altitudinal patterns of vascular plant species richness and species range in Qinling Xiaolongshan Reserve, and examined the relationships between species richness and their distributional middle points in altitudinal bands for different fauna, taxonomic units and growth forms and tested the Rapoport's rule by using Stevens' method, Pagel's method, mid-point method and cross-species method. The results showed that the species richness of vascular plants except small-range species showed a unimodal pattern along the altitude in Qinling Xiaolongshan Reserve and the highest proportion of small-range species was found at the lower altitudinal bands and at the higher altitudinal bands. Due to different assemblages and examining methods, the relationships between species distributing range sizes and the altitudes were different. Increasing taxonomic units was easier to support Rapoport's rule, which was related to niche differences that the different taxonomic units occupied. The mean species range size of angiosperms showed a unimodal pattern along the altitude, while those of the gymnosperms and pteridophytes were unclearly regular. The mean species range size of the climbers was wider with the increasing altitude, while that of the shrubs which could adapt to different environmental situations was not sensitive to the change of altitude. Pagel's method was easier to support the Rapoport's rule, and then was Steven's method. On the contrary, due to the mid-domain effect, the results of the test by using the mid-point method showed that the mean species range size varied in a unimodal pattern along the altitude, which didn't support the Rapoport's rule, and because of the scatter-spot impact, the explanatory power of the cross-species method was much lower.


Subject(s)
Altitude , Biodiversity , Plants/classification , China , Geography
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