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1.
PLoS One ; 19(5): e0303447, 2024.
Article in English | MEDLINE | ID: mdl-38753727

ABSTRACT

This paper studies the recycling and remanufacturing mode and sales channel issues in the closed-loop supply chain. Specifically, this study establishes an e-commerce closed-loop supply chain consisting of a manufacturer and an e-commerce platform, and divides the recycling model into recycling by the manufacturer or recycling by the platform. Considering two common sales models in e-commerce platforms: the resale model and agency model, combined with the recycling model, four different research scenarios are formed. We use backward induction to solve the Stackelberg game problem and explore the remanufacturing and channel strategies of the manufacturer and the e-commerce platform. The research results show that for the manufacturer, under the same recycling model, when consumers' preference for remanufactured products and the sensitivity of recycling volume to recycling prices are low, he will prefer the resale model. Under the same sales model, the manufacturer always prefers the recycling model in which he is responsible for recycling. However, the choice of platform is contrary to that of the manufacturer. In the resale model, both the manufacturer and the platform will choose to recycle by themselves, which cannot achieve a win-win situation. Under the agency model, when consumers' preference for remanufactured products is high and the sensitivity coefficient of recycling volume to recycling price is low, supply chain members can achieve a win-win situation, and the scope of the win-win situation decreases as the unit production cost of new products increases. In addition, rising consumer preference for remanufactured products will lead to lower consumer surplus.


Subject(s)
Commerce , Recycling , Consumer Behavior , Humans , Models, Theoretical
2.
J Am Chem Soc ; 146(9): 5823-5833, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38174701

ABSTRACT

The biological significance of self-assembled protein filament networks and their unique mechanical properties have sparked interest in the development of synthetic filament networks that mimic these attributes. Building on the recent advancement of autoaccelerated ring-opening polymerization of amino acid N-carboxyanhydrides (NCAs), this study strategically explores a series of random copolymers comprising multiple amino acids, aiming to elucidate the core principles governing gelation pathways of these purpose-designed copolypeptides. Utilizing glutamate (Glu) as the primary component of copolypeptides, two targeted pathways were pursued: first, achieving a fast fibrillation rate with lower interaction potential using serine (Ser) as a comonomer, facilitating the creation of homogeneous fibril networks; and second, creating more rigid networks of fibril clusters by incorporating alanine (Ala) and valine (Val) as comonomers. The selection of amino acids played a pivotal role in steering both the morphology of fibril superstructures and their assembly kinetics, subsequently determining their potential to form sample-spanning networks. Importantly, the viscoelastic properties of the resulting supramolecular hydrogels can be tailored according to the specific copolypeptide composition through modulations in filament densities and lengths. The findings enhance our understanding of directed self-assembly in high molecular weight synthetic copolypeptides, offering valuable insights for the development of synthetic fibrous networks and biomimetic supramolecular materials with custom-designed properties.


Subject(s)
Hydrogels , Peptides , Hydrogels/chemistry , Peptides/chemistry , Amino Acids , Glutamic Acid/chemistry , Alanine/chemistry
3.
Inorg Chem ; 62(15): 5920-5930, 2023 Apr 17.
Article in English | MEDLINE | ID: mdl-37017463

ABSTRACT

Triplet photovoltaic materials have been rarely investigated in organic solar cells (OSCs) because the role and mechanism of triplet excitons are still unclear. Cyclometalated heavy metal complexes with triplet features are expected to increase exciton diffusion lengths and improve exciton dissociation in OSCs, while the power conversion efficiencies (PCEs) of their bulk-heterojunction (BHJ) OSCs are still limited to <4%. We herein report an octahedral homoleptic tris-Ir(III) complex TBz3Ir as a donor material for BHJ OSCs with a PCE of over 11%. In comparison with the planar organic TBz ligand and heteroleptic TBzIr, TBz3Ir demonstrates the highest PCE and best device stability in both fullerene- and non-fullerene-based devices, owing to the long triplet lifetime, enhanced optical absorption, increased charge transport, and improved film morphology. From transient absorption, triplet excitons were deduced to participate in the photoelectric conversion process. In particular, the more significant 3D structure of TBz3Ir induces an unusual film morphology in TBz3Ir:Y6 blends, showing obviously large domain sizes suitable for triplet excitons. Thus, a high PCE of 11.35% with a high circuit current density of 24.17 mA cm-2 and a fill factor of 0.63 is achieved for small-molecular Ir complex-based BHJ OSCs.

4.
Article in English | MEDLINE | ID: mdl-36981634

ABSTRACT

Remanufacturing, as an effective way to save resources and alleviate environmental pollution, has gradually become a sustainable practice. Environmental education contributes to the development of remanufacturing by increasing the number of consumers willing to purchase remanufactured products (RPs). However, the incumbent manufacturer usually has limited remanufacturing capability together with yield uncertainty, making a third-party remanufacturer (3PR) an alternate channel choice. This study develops an analytical model to examine the effects of environmental education on a retailer's choice of remanufacturing channels under in-store competition. Results show that consumer environmental education has the potential to significantly improve the retailer and supply chain profits, and temperate environmental education is always desirable for 3PR. The introduction of 3PR benefits the consumer when the retailer's remanufacturing technology level is low. Furthermore, when the environmental impact of defective RPs is relatively high, and environmental education is temperate, selecting a 3PR will enhance environmental sustainability. This study also shows that 3PR can help achieve a win-win situation when environmental education and consumer acceptance of RPs are both in a certain range.


Subject(s)
Commerce , Consumer Behavior , Commerce/methods
5.
Nanomaterials (Basel) ; 12(5)2022 Mar 02.
Article in English | MEDLINE | ID: mdl-35269328

ABSTRACT

The introduction of inorganic additive or nanoparticles into fluorine-free proton exchange membranes (PEMs) can improve proton conductivity and have considerable effects on the performance of polymer electrolyte membrane fuel cells. Based on the sol-gel method and in situ polycondensation, novel cross-linked PEM and nanocomposite PEMs based on a sulfonated polysulfone (SPSU) matrix were prepared by introducing graphene oxide (GO) polymeric brushes and incorporating Pt-TiO2 nanoparticles into an SPSU matrix, respectively. The results showed that the incorporation of Pt-TiO2 nanoparticles could obviously enhance self-humidifying and thermal stability. In addition, GO polymer brushes fixed on polymeric PEM by forming a cross-linked network structure could not only solve the leakage of inorganic additives during use and compatibility problem with organic polymers, but also significantly improve proton conductivity and reduce methanol permeability of the nanocomposite PEM. Proton conductivity, water uptake and methanol permeability of the nanocomposite PEM can be up to 6.93 mS cm-1, 46.58% and be as low as 1.4157 × 10-6 cm2 s-1, respectively, which represent increases of about 70%, about 22% and a decrease of about 40%, respectively, compared with that of primary SPSU. Therefore, the synergic action of the covalent cross-linking, GO polymer brush and nanoparticles can significantly and simultaneously improve the overall performance of the composite PEM.

6.
Environ Sci Pollut Res Int ; 29(27): 40701-40710, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35084680

ABSTRACT

We aimed to examine PM2.5 exposure, blood pressure (SBP and DBP) measurement, and hypertension risk factors and to assess the association between PM2.5 exposure and hypertension among young adults. The mean SBP was 117.78 mmHg, with 11.22% high-normal blood pressure (prehypertension) and 2.51% hypertension (≥ 140 mmHg). DBP was 75.48 mmHg with 26.37% prehypertension and 4.53% hypertension (≥ 90 mmHg). The median PM2.5 in the past year was 31.79 µg/m3, with highest in winter (49.33 µg/m3), followed by spring (37.34 µg/m3), autumn (29.64 µg/m3), and summer (24.33 µg/m3). Blood pressure was positively correlated with age, height, weight, BMI, daily smoking, alcohol consumption, mental stress, and staying up in the past 1 year, and negatively with season-specific temperature. After adjustment for the covariates, each 10 µg/m3 increase in PM2.5 was associated with SBP (day 1 = 1.07 mmHg, day 3 = 1.25 mmHg, day 5 = 1.01 mmHg) and DBP (day 1 = 1.06 mmHg, day 3 = 1.28 mmHg, day 5 = 1.29 mmHg, day 15 = 0.87 mmHg, day 30 = 0.56 mmHg). Exposure in winter and the past year was associated with 1.21 mmHg and 0.95 increase mmHg in SBP, respectively. Logistic models showed for every 1 µg/m3 increase of PM2.5, SBP in day 1 and day 5 was increased by 6% and 4%, and DPB by 3% and 16%, respectively. SBP was increased by 8% in spring and 19% in winter, and DBP was increased by 7% in winter. Our data suggest a certain prevalence of pre- or hypertension among young population, which is associated with short-term fluctuation and season-specific exposure of PM2.5.


Subject(s)
Hypertension , Prehypertension , Blood Pressure , Humans , Hypertension/chemically induced , Hypertension/epidemiology , Particulate Matter/analysis , Prehypertension/chemically induced , Prehypertension/epidemiology , Temperature , Young Adult
7.
Biomacromolecules ; 23(1): 196-209, 2022 01 10.
Article in English | MEDLINE | ID: mdl-34964619

ABSTRACT

In cells, actin and tubulin polymerization is regulated by nucleation factors, which promote the nucleation and subsequent growth of protein filaments in a controlled manner. Mimicking this natural mechanism to control the supramolecular polymerization of macromolecular monomers by artificially created nucleation factors remains a largely unmet challenge. Biological nucleation factors act as molecular scaffolds to boost the local concentrations of protein monomers and facilitate the required conformational changes to accelerate the nucleation and subsequent polymerization. An accelerated assembly of synthetic poly(l-glutamic acid) into amyloid fibrils catalyzed by cationic silica nanoparticle clusters (NPCs) as artificial nucleation factors is demonstrated here and modeled as supramolecular polymerization with a surface-induced heterogeneous nucleation pathway. Kinetic studies of fibril growth coupled with mechanistic analysis demonstrate that the artificial nucleators predictably accelerate the supramolecular polymerization process by orders of magnitude (e.g., shortening the assembly time by more than 10 times) when compared to the uncatalyzed reaction, under otherwise identical conditions. Amyloid-like fibrillation was supported by a variety of standard characterization methods. Nucleation followed a Michaelis-Menten-like scheme for the cationic silica NPCs, while the corresponding anionic or neutral nanoparticles had no effect on fibrillation. This approach shows the effectiveness of charge-charge interactions and surface functionalities in facilitating the conformational change of macromolecular monomers and controlling the rates of nucleation for fibril growth. Molecular design approaches like these inspire the development of novel materials via biomimetic supramolecular polymerizations.


Subject(s)
Amyloid , Peptides , Amyloid/chemistry , Amyloidogenic Proteins , Kinetics , Peptides/chemistry , Polymerization
8.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3566-3576, 2021 Jul.
Article in Chinese | MEDLINE | ID: mdl-34402279

ABSTRACT

Medicinal plants are beneficial to human health. However,most of the major producing regions of medicinal plants suffer from rust disease,which threatens the yield and quality of Chinese medicinal materials,thus causes huge economic loss,and hinders the sustainable development of the Chinese medicine industry. By the end of 2020,rust disease had been reported in medicinal plants of 76 species and 33 families. In the 76 species,79 rust pathogens were detected. The majority of these pathogens belonged to Puccinia( 33,39. 24%),Coleosporium( 14,15. 19%),and Aecidium( 11,13. 92%). Of these 79 rust pathogens,10 were autoecious and 13 were heteroecious. Through literature research,this study reviewed the symptoms,pathogen species,severity and distribution,prevalence and occurrence conditions,and control measures of rust disease in medicinal plants,and thereby summarized the research status of rust disease in medicinal plants and the gap with other plants,which is expected to serve as a reference for further research on rust disease in medicinal plants.


Subject(s)
Basidiomycota , Plants, Medicinal , Basidiomycota/genetics , Humans , Plant Diseases
9.
Dalton Trans ; 50(28): 9871-9880, 2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34195721

ABSTRACT

Cyclometalated iridium(iii) complexes have been investigated as promising electron donor (D) materials in organic solar cells (OSCs) due to their unique octahedral configuration for optimized morphology and their significantly long lifetimes potentially for enhanced exciton dissociation. However, the application as electron acceptor (A) materials has never been reported. In order to fill this blank, herein, two cyclometalated heteroleptic Ir complexes, TRIr and 2TRIr, based on electron donating-accepting type organic ligands with different π-conjugation lengths are reported as electron acceptor materials in comparison with their corresponding main organic ligands. The two Ir complexes exhibit suitable HOMO/LUMO energy levels of -5.55/-3.47 eV and -5.44/-3.48 eV, which are ∼0.1 eV higher in the HOMO and ∼0.15 eV deeper in the LUMO than the TR and 2TR ligands, respectively. 2TRIr with extended ligand π-conjugation displays a poor triplet feature, while TRIr demonstrates obvious metal-to-ligand charge transfer (MLCT) transition absorption, with a triplet component photoluminescence (PL) lifetime of 85 ns in neat films. When blended with PBDB-T in bulk heterojunction (BHJ) OSCs, the power conversion efficiencies (PCEs) are 2-3 times higher than their relevant ligands, with values of 1.20% and 1.62% for TRIr and 2TRIr, and 0.58% and 0.47% for the TR and 2TR ligand-based devices, respectively. TRIr and 2TRIr based active layer blends exhibit poorer hole and electron mobilities, whereas compared with their relatively linear planar ligands, both of the two octahedral Ir complexes exhibit an optimized surface morphology for less bimolecular recombination and more efficient exciton dissociation, thus contributing to improved photovoltaic performance.

10.
Article in English | MEDLINE | ID: mdl-31061157

ABSTRACT

TBI-166, derived from riminophenazine analogues, is under development in a phase I clinical trial in China. TBI-166 showed more potent anti-tuberculosis (anti-TB) activity than did clofazimine in in vitro and animal experiments. To identify potent regimens containing TBI-166 in TB chemotherapy, TBI-166 was assessed for pharmacological interactions in vitro and in vivo with several anti-TB drugs, including isoniazid (INH), rifampin (RFP), bedaquiline (BDQ), pretomanid (PMD), linezolid (LZD), and pyrazinamide (PZA). Using an in vitro checkerboard method, we found that TBI-166 did not show antagonism or synergy with the tested drugs. The interaction relationship between TBI-166 and each drug was indifferent. In in vivo experiments, aerosol infection models with BALB/c and C3HeB/FeJNju mice were established, testing drugs were administered either individually or combined in treatments containing TBI-166 and one, two, or three other drugs, and the bactericidal activities were determined after 4- and 8-week therapeutic treatments. In BALB/c mice, five TBI-166-containing regimens-TBI-166+BDQ, TBI-166+PZA, TBI-166+BDQ+LZD, TBI-166+BDQ+PMD, and TBI-166+BDQ+PMD+LZD-showed significantly more potent efficacy after 4 weeks of treatment compared to the control regimen, INH+RFP+PZA. At the end of an 8-week treatment, lung log CFU counts decreased to undetectable levels in mice treated with each of the five regimens. The rank order of the potency of the five regimens was as follows: TBI-166+BDQ+LZD > TBI-166+BDQ > TBI-166+PZA > TBI-166+BDQ+PMD+LZD > TBI-166+BDQ+PMD. In C3HeB/FeJNju mice, TBI-166+BDQ+LZD was also the most effective of the TBI-166-containing regimens. In conclusion, five potent chemotherapy regimens that included TBI-166 were identified. The TBI-166+BDQ+LZD regimen is recommended for further testing in a TBI-166 phase IIb clinical trial.


Subject(s)
Antitubercular Agents/pharmacology , Mycobacterium tuberculosis/drug effects , Tuberculosis/drug therapy , Animals , China , Female , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Microbial Sensitivity Tests/methods , Tuberculosis/microbiology
11.
RSC Adv ; 8(28): 15740-15753, 2018 Apr 23.
Article in English | MEDLINE | ID: mdl-35539468

ABSTRACT

Functional polymer brush modified graphene oxide (FPGO) with functional linear polysiloxane brushes was synthesized via surface precipitation polymerization (sol-gel) and chemical modification. Then, FPGO was covalently cross-linked to the sulfonated polysulfone (SPSU) matrix to obtain novel SPSU/FPGO cross-linked nanocomposite membranes. Meanwhile, SPSU/GO composite membranes and a pristine SPSU membrane were fabricated as control groups. Reduced agglomeration of the inorganic filler and better interfacial interaction, which are benefit to increase diffusion resistance of methanol and to generate continuous channels for fast proton transportation at elevated temperature, were observed in SPSU/FPGO cross-linked membranes. Moreover, the enhanced membrane stability (thermal, oxidative and dimensional stability) and good mechanical performance also guaranteed their proton conducting durability. It is noteworthy that the SPSU/FPGO-1 cross-linked membrane possesses the best comprehensive properties among all the prepared membranes and Nafion®117, it acquires the highest proton conductivity of 0.462 S cm-1 at 90 °C under hydrated conditions together with a low methanol permeability of 1.71 × 10-6 cm2 s-1 at 30 °C. The resulting high membrane selectivity displays the great potential of the SPSU/FPGO cross-linked membrane for DMFCs application.

12.
Zhong Yao Cai ; 38(10): 2042-7, 2015 Oct.
Article in Chinese | MEDLINE | ID: mdl-27254914

ABSTRACT

OBJECTIVE: To investigate the damage and community structure of weeds in Scrophularia ningpoensis fields in Nanchuan, Chongqing. METHODS: From 2013 to 2014, an investigation was carried out by inverted W-9 point sampling method to study the weed species. RESULTS: 96 weed species belonged to 75 genera of 30 families were observed, including 18 species of Asteraceae weeds (accounted for 18.75%), 10 species of Poaceae weeds (accounted for 10.42%). Moreover, there were 57 species of annual weeds (accounted for 59.38%) and 39 species of perennial weeds (accounted for 40.63%). The overall abundance of Erigeron annuus, Digitaria adscendens, Torilis scabra, Polygonum nepalense, Ranunculus japonicas, Stellaria media and Commelina communis were relatively higher than that of the others. CONCLUSION: The difference of weed species and community structure might result from the physical and chemical characteristics of soil, moisture content, cropping system, tillage type, environmental and climatic conditions, crop distribution and weed control.


Subject(s)
Biodiversity , Plant Weeds/classification , Scrophularia , Agriculture , Asteraceae/classification , Asteraceae/growth & development , China , Plant Weeds/growth & development , Poaceae/classification , Poaceae/growth & development , Soil
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