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1.
Langmuir ; 40(16): 8738-8750, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38602229

RESUMO

In this work, a novel birnessite-type MnO2 modified corn husk sustainable biomass fiber (MnO2@CHF) adsorbent was fabricated for efficient cadmium (Cd) removal from aquatic environments. MnO2@CHF was designed from KMnO4 hydrothermally treated with corn husk fibers. Various characterization revealed that MnO2@CHF possessed the hierarchical structure nanosheets, large specific surface area, and multiple oxygen-containing functional groups. Batch adsorption experimental results indicated that the highest Cd (II) removal rate could be obtained at the optimal conditions of adsorbent amount of 0.200 g/L, adsorption time of 600 min, pH 6.00, and temperature of 40.0 °C. Adsorption isotherm and kinetics results showed that Cd (II) adsorption behavior on MnO2@CHF was a monolayer adsorption process and dominated by chemisorption and intraparticle diffusion. The optimum adsorption capacity (Langmuir model) of Cd (II) on MnO2@CHF was 23.0 mg/g, which was higher than those of other reported common biomass adsorbent materials. Further investigation indicated that the adsorption of Cd (II) on MnO2@CHF involved mainly ion exchange, surface complexation, redox reaction, and electrostatic attraction. Moreover, the maximum Cd (II) removal rate on MnO2@CHF from natural river samples (Xicheng Canal) could reach 59.2% during the first cycle test. This study showed that MnO2@CHF was an ideal candidate in Cd (II) practical application treatment, providing references for resource utilization of agricultural wastes for heavy metal removal.

2.
Inorg Chem ; 63(38): 17692-17700, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39230933

RESUMO

The etching effect has the capability to control atom doping and trigger phase transformation, thereby enhancing the electrocatalytic reaction. Herein, iron-doped cobalt selenide (Fe-CoSe2) nanoparticle-decorated carbon nanofibers (Fe-CoSe2/CNFs) are synthesized by assembling an FeCo-Prussian blue analogue (FeCo-PBA) cube precursor with polyacrylonitrile fibers and then treating with hydrochloric acid, followed by gas phase selenization. The Fe-CoSe2/CNFs catalyst exhibits a large surface area and a porous structure, facilitating the permeation of electrolytes. Moreover, orthorhombic CoSe2 is obtained, which is in favor of improving the oxygen evolution reaction (OER). By modulating the etching time, the ideal crystal phase and the optimal amount of the dopant (Fe) can be achieved, thus showing favorable OER activity. Specifically, the Fe-CoSe2/CNFs electrocatalyst enables high electrocatalytic activity for the OER with a low overpotential of 263 mV to drive a current density of 10 mA cm-2 in 1 M KOH. A small Tafel slope of 51 mV dec-1 shows fast charge transfer kinetics. Density functional theory (DFT) calculations reveal that Fe-doped orthorhombic CoSe2(111) can modulate the electron structure, contributing to OH- adsorption ability. Given this, a strategy for phase transformation induced by etching technology is proposed to improve the intrinsic activity of the catalyst.

3.
Inorg Chem ; 63(3): 1682-1691, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38189122

RESUMO

One of the crucial parts of the electrochemically focused energy conversion and storage system is the hydrogen evolution reaction. The further exploration of electrocatalysts made of nonprecious metals could help to bring the technology closer to industrialization. Here, we present an effective hydrogen evolution reaction (HER) electrocatalyst that employs hydrothermal and phosphorization steps to create three-dimensional (3D) porous MoP2-NiCoP heterostructure nanosheets on nickel foam (MoP2-NiCoP/NF). H2O-dissociation and H-adsorption were effectively achieved due to the distinctive interface engineering between NiCoP and MoP2, which functions as a channel for immediate electron transfer. Compared to the single-component MoP2 and NiCoP, the synergistic interaction between the heterogeneous components coupling and the 3D porous structure enables MoP2-NiCoP/NF to exhibit satisfactory catalytic activity with an ultralow overpotential of 50 mV at 10 mA cm-2, which is close to the commercial Pt/C catalyst in alkaline media. More importantly, it exhibits good stability, with the ability to be electrolyzed in 1.0 M KOH electrolyte for 24 h without a significant change in overpotential. This study offers directions for the design of low-cost, high-activity, transition metal phosphides (TMPs)-based HER catalyst alternatives for future practical applications.

4.
Inorg Chem ; 63(20): 9346-9354, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38717960

RESUMO

Electrochemical water splitting is a possible way of realizing sustainable and clean hydrogen production but is challenging, because a highly active and durable electrocatalyst is essential. In this work, we integrated heterogeneous engineering and vacancy defect strategies to design and fabricate a heterostructure electrocatalyst (CoPv-MoxPv/CNT) with abundant phosphorus vacancies attached to carbon nanotubes (CNTs). The vacancy defects enabled the optimization of the electronic structure; thereby, the electron-rich low-valent metal sites enhanced the ability of nonmetallic P to capture proton H. Meanwhile, the heterogeneous interface between bimetallic phosphides and CNTs realized rapid electron transfer. In addition, the Co, Mo, and P active species in the electrocatalytic process exposed increased amounts of active sites featuring porous nanosheet structures, which facilitated the adsorption of reaction intermediates and thus enhanced the hydrogen evolution reaction performance. In particular, the optimized CoPv-MoxPv/CNT catalyst possesses an overpotential of 138 mV at a current density of 10 mA cm-2 and long-term stability for 24 h. This work offers insights and possibilities for the engineering and exploration of transition metal-based electrocatalysts through combining multiple synergistic strategies.

5.
J Appl Microbiol ; 135(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38632051

RESUMO

AIMS: We aimed to develop an effective bacterial combination that can combat Fusarium oxysporum infection in watermelon using in vitro and pot experiments. METHODS AND RESULTS: In total, 53 strains of Bacillus and 4 strains of Pseudomonas were screened. Pseudomonas strains P3 and P4 and Bacillus strains XY-2-3, XY-13, and GJ-1-15 exhibited good antagonistic effects against F. oxysporum. P3 and P4 were identified as Pseudomonas chlororaphis and Pseudomonas fluorescens, respectively. XY-2-3 and GJ-1-15 were identified as B. velezensis, and XY-13 was identified as Bacillus amyloliquefaciens. The three Bacillus strains were antifungal, promoted the growth of watermelon seedlings and had genes to synthesize antagonistic metabolites such as bacilysin, surfactin, yndj, fengycin, iturin, and bacillomycin D. Combinations of Bacillus and Pseudomonas strains, namely, XY-2-3 + P4, GJ-1-15 + P4, XY-13 + P3, and XY-13 + P4, exhibited a good compatibility. These four combinations exhibited antagonistic effects against 11 pathogenic fungi, including various strains of F. oxysporum, Fusarium solani, and Rhizoctonia. Inoculation of these bacterial combinations significantly reduced the incidence of Fusarium wilt in watermelon, promoted plant growth, and improved soil nutrient availability. XY-13 + P4 was the most effective combination against Fusarium wilt in watermelon with the inhibition rate of 78.17%. The number of leaves; aboveground fresh and dry weights; chlorophyll, soil total nitrogen, and soil available phosphorus content increased by 26.8%, 72.12%, 60.47%, 16.97%, 20.16%, and 16.50%, respectively, after XY-13 + P4 inoculation compared with the uninoculated control. Moreover, total root length, root surface area, and root volume of watermelon seedlings were the highest after XY-13 + P3 inoculation, exhibiting increases by 265.83%, 316.79%, and 390.99%, respectively, compared with the uninoculated control. CONCLUSIONS: XY-13 + P4 was the best bacterial combination for controlling Fusarium wilt in watermelon, promoting the growth of watermelon seedlings, and improving soil nutrient availability.


Assuntos
Bacillus , Citrullus , Resistência à Doença , Fusarium , Doenças das Plantas , Pseudomonas , Fusarium/crescimento & desenvolvimento , Citrullus/microbiologia , Citrullus/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Bacillus/fisiologia , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/fisiologia , Antibiose , Pseudomonas fluorescens/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Antifúngicos/farmacologia
6.
Inorg Chem ; 62(1): 601-608, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36538349

RESUMO

It is necessary to develop an efficient hydrogen evolution catalyst to improve the efficiency of the hydrogen evolution reaction (HER). Herein, a MoS2 nanosheet is decorated on the Pt-doping biomass yeast cells (MoS2@Pt/YC) via a simple hydrothermal process. Reducing the noble metal loading without compromising its performance is a challenging task. The smooth surface of YCs is conducive to the growth of MoS2 nanosheets, and its functional groups provide attachment sites for metal Pt. The Pt/YC is covered with MoS2 nanosheets, thus improving the exposed active sites for HER. The obtained MoS2@Pt/YC delivers a competitive overpotential of 118 mV at the benchmark current density of 10 mA cm-2 and achieves a small Tafel slope of 74 mV dec-1, indicating the great HER performance of MoS2@Pt/YC. Moreover, MoS2@Pt/YC shows robust stability after 24 h of continuous operation toward HER in acidic solution. By introducing transition metal sulfides with high specific surface area, the loading of precious metals can be reduced without compromising properties. This work provides a method to design Pt-doping HER electrocatalysts through a simple method. The facile preparation process for MoS2@Pt/YC and its outstanding performance allow it to be a promising electrocatalyst for practical HER application.


Assuntos
Carbono , Molibdênio , Biomassa , Hidrogênio , Saccharomyces cerevisiae
7.
Inorg Chem ; 62(49): 20250-20257, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38019575

RESUMO

MXenes exhibit unique layered structures and excellent electrical conductivity, and their multiple surface termination groups are favorable for hosting impressive performance for electrochemical reactions. Therefore, a two-dimensional (2D) layered MXene-based catalyst may become a novel high-efficiency electrocatalyst to replace traditional noble metal electrocatalysts. In this work, a transition metal chalcogenide (MoS2/CuS) and MXene are combined to prepare a 2D electrocatalyst (MoS2/CuS/MXene) for the hydrogen evolution reaction (HER). MXene exhibited a large specific surface area in the shape of an accordion, which was very beneficial for the growth of nanomaterials. CuS/MXene promoted electron transfer and improved the exposed active site for HER. The exposed MoS2 edges exhibited a high chemical adsorption capacity, which is conducive to HER. Electrochemical tests reveal that the MoS2/CuS/MXene electrocatalyst can reduce the charge transfer resistance toward the HER and increase active sites for HER, leading to enhancing the catalytic performance. The MoS2/CuS/MXene electrocatalyst affords an efficient HER with a low overpotential (115 mV@10 mA cm-2). This work offers a new idea to create layered transition metal chalcogenide- and MXene-based electrocatalysts for HER.

8.
Inorg Chem ; 61(13): 5352-5362, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35306810

RESUMO

The hydrogen evolution reaction (HER) is significantly influenced by the evolved H2 bubble diffusion rate on the surface of the electrode, which involves the blocking and release of the active site at the catalytic interface. Rational design of nanostructured catalysts could not only sharply enhance the specific surface area but also provide large amounts of channels for gas release. Herein, NiCo-nanowire-derived multimetal chalcogenides grown in situ on carbon cloth [denoted as (NiCo)S2@MoS2/CC] are presented by serial hydrothermal methods. The obtained hierarchical nanowire array architecture affords abundant surface-active sites and is conducive to permeate electrolytes. The surface adsorption/desorption behavior of the heterostructure catalyst was optimized through regulating MoS2 concentration. Owing to the synergistic effect of metal Ni and Co and the interaction of the (NiCo)S2@MoS2 heterostructure, (NiCo)S2@MoS2/CC-2 delivers a relatively low overpotential of 74 mV at a current density of 10 mA cm-2 and displays a small Tafel slope of 54 mV dec-1 for HER catalysis, surpassing that of the recently reported MoS2-based electrocatalysts. Such a strategy through nanostructure optimization and electron interaction of the heterostructure could improve the electrocatalytic HER performance for multimetal chalcogenides in an alkaline medium.

9.
Inorg Chem ; 61(36): 14436-14446, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36038523

RESUMO

Electrocatalytic water splitting is considered a promising approach to obtain clean and sustainable hydrogen energy. The integration of optimal nanoarchitecture and multicomponent synergy has been a significant factor for designing a bifunctional electrocatalyst to promote the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER). In particular, the charge migration, mass transfer, and gas release rate in the catalyzing process are closely correlated with the architecture of the catalyst. Here, ZIF-67-derived N-doped carbon nanofiber-supported (NiCo)S2 nanosheet [(NiCo)S2/NCNF] as a bifunctional electrocatalyst was synthesized using electrospinning, template etching, and subsequent gas sulfidation method. The hierarchical hybrid nanofiber with inner hollow cubes and outer nanosheets provides easy electron penetration, high charge/mass transportation efficiency, and robust structure stability. Furthermore, the MOF-derived carbon-encapsuled bimetal-sulfide and the synergistic effect of double active centers are conducive to an exceptional performance, showing low overpotentials of 177 and 203 mV to drive a current density of 10 mA cm-2 and robust stability for the HER and OER, respectively. Meanwhile, the (NiCo)S2/NCNF electrodes exhibit a small voltage of 1.61 V for overall water splitting activity with an electrolyzer cell at current densities of 10 mA cm-2 over 12 h. This work presents novel insights into the bifunctional catalyst for promoting the overall water splitting via a MOF-derived nanoarchitecture and multicomponent synergy.

10.
Proc Natl Acad Sci U S A ; 116(1): 177-186, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30514813

RESUMO

Phenotypic variation is critical for the long-term persistence of species and populations. Anthropogenic activities have caused substantial shifts and reductions in phenotypic variation across diverse taxa, but the underlying mechanism(s) (i.e., phenotypic plasticity and/or genetic evolution) and long-term consequences (e.g., ability to recover phenotypic variation) are unclear. Here we investigate the widespread and dramatic changes in adult migration characteristics of wild Chinook salmon caused by dam construction and other anthropogenic activities. Strikingly, we find an extremely robust association between migration phenotype (i.e., spring-run or fall-run) and a single locus, and that the rapid phenotypic shift observed after a recent dam construction is explained by dramatic allele frequency change at this locus. Furthermore, modeling demonstrates that continued selection against the spring-run phenotype could rapidly lead to complete loss of the spring-run allele, and an empirical analysis of populations that have already lost the spring-run phenotype reveals they are not acting as sustainable reservoirs of the allele. Finally, ancient DNA analysis suggests the spring-run allele was abundant in historical habitat that will soon become accessible through a large-scale restoration (i.e., dam removal) project, but our findings suggest that widespread declines and extirpation of the spring-run phenotype and allele will challenge reestablishment of the spring-run phenotype in this and future restoration projects. These results reveal the mechanisms and consequences of human-induced phenotypic change and highlight the need to conserve and restore critical adaptive variation before the potential for recovery is lost.


Assuntos
Adaptação Fisiológica , Ecossistema , Salmão , Adaptação Fisiológica/genética , Alelos , Migração Animal , Animais , Loci Gênicos/genética , Variação Genética/genética , Oregon , Salmão/genética
11.
Proc Biol Sci ; 288(1945): 20202398, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33622133

RESUMO

The timing of reproduction influences key evolutionary and ecological processes in wild populations. Variation in reproductive timing may be an especially important evolutionary driver in the marine environment, where the high mobility of many species and few physical barriers to migration provide limited opportunities for spatial divergence to arise. Using genomic data collected from spawning aggregations of Pacific herring (Clupea pallasii) across 1600 km of coastline, we show that reproductive timing drives population structure in these pelagic fish. Within a specific spawning season, we observed isolation by distance, indicating that gene flow is also geographically limited over our study area. These results emphasize the importance of considering both seasonal and spatial variation in spawning when delineating management units for herring. On several chromosomes, we detected linkage disequilibrium extending over multiple Mb, suggesting the presence of chromosomal rearrangements. Spawning phenology was highly correlated with polymorphisms in several genes, in particular SYNE2, which influences the development of retinal photoreceptors in vertebrates. SYNE2 is probably within a chromosomal rearrangement in Pacific herring and is also associated with spawn timing in Atlantic herring (Clupea harengus). The observed genetic diversity probably underlies resource waves provided by spawning herring. Given the ecological, economic and cultural significance of herring, our results support that conserving intraspecific genetic diversity is important for maintaining current and future ecosystem processes.


Assuntos
Ecossistema , Pesqueiros , Animais , Peixes/genética , Variação Genética , Reprodução
12.
Proc Natl Acad Sci U S A ; 112(40): 12344-8, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26392548

RESUMO

Salmon represented a critical resource for prehistoric foragers along the North Pacific Rim, and continue to be economically and culturally important; however, the origins of salmon exploitation remain unresolved. Here we report 11,500-y-old salmon associated with a cooking hearth and human burials from the Upward Sun River Site, near the modern extreme edge of salmon habitat in central Alaska. This represents the earliest known human use of salmon in North America. Ancient DNA analyses establish the species as Oncorhynchus keta (chum salmon), and stable isotope analyses indicate anadromy, suggesting that salmon runs were established by at least the terminal Pleistocene. The early use of this resource has important implications for Paleoindian land use, economy, and expansions into northwest North America.


Assuntos
DNA/química , Fósseis , Oncorhynchus keta/genética , Coluna Vertebral/metabolismo , Alaska , Animais , Sequência de Bases , Isótopos de Carbono , Citocromos b/classificação , Citocromos b/genética , DNA/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Proteínas de Peixes/genética , Geografia , Haplótipos , Humanos , Dados de Sequência Molecular , Isótopos de Nitrogênio , Oncorhynchus keta/anatomia & histologia , Filogenia , Datação Radiométrica/métodos , Rios , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Coluna Vertebral/anatomia & histologia
13.
J Colloid Interface Sci ; 677(Pt B): 1005-1013, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39178664

RESUMO

Electrochemical water splitting for hydrogen production is an ideal process for clean energy production. However, highly active and low-cost electrocatalysts are essential and challenging. In this work, a multi-component Cu-based catalyst (Ru-M-C-Cu), synergized with ruthenium (Ru) heteroatom doping, was synthesized via a facile immersion-calcination-immersion method. Based on the cotton biomass substrate, a hollow tubular structure was obtained. By virtue of its distinctive structure and high carbon content, cotton biomass assumed a dual role as a sacrificial template and a reducing agent in the eco-friendly synthesis of electrocatalysts, which was instrumental in the creation of a multi-component system augmented by heteroatom doping. The multi-component system was constructed by in-situ transformation and redox reaction during calcination in an oxygen-free environment. The Ru-M-C-Cu catalyst exhibited a competitive overpotential of 108 mV at a current density of 10 mA cm-2 for alkaline hydrogen evolution reaction (HER). The satisfactory catalytic performance of Ru-M-C-Cu can be attributed to the fact that the Ru-O-Cu catalytic centers enhanced the adsorption and desorption abilities of the Cu-O active sites toward hydrogen. Furthermore, the hollow tubular structure allowed the electrolyte to make full contact with the active sites of the Ru-M-C-Cu catalyst, thus accelerated the HER kinetics. The catalyst showed structural and chemical stability after a 12-hour successive test. Besides, the production cost of Ru-M-C-Cu was significantly reduced by 99.1 % than that of commercial 20 % Pt/C, showing the potential as an alternative catalyst by offering a more accessible and sustainable source. This work provides a new design of sustainable low-budget electrocatalysts with the proposed strategies expected for producing clean and renewable hydrogen energy.

14.
J Colloid Interface Sci ; 669: 935-943, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38754146

RESUMO

Construction of multi-component heterostructures is an effective strategy for electrocatalysts to improve both the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) activity at the anode. Herein, an efficient bifunctional electrocatalyst towards overall water/seawater splitting (OW/SS) is reported with strategy of heterostructure construction (ruthenium/nickel phosphorus) on nickel hydroxide (Ni(OH)2). With the unique hydrolysis layer (Ni(OH)2), the processes of H2O hydrolysis and the adsorption/desorption of H*/O-containing intermediates (OH, O, OOH) were greatly boosted by Ru and P sites, which acted as the catalytic active centers of OER and HER, respectively. In addition, the electronic structure reconfiguration was realized through the strong interaction between multi-interfaces. For alkaline HER at the current density of 10 mA cm-2, the overpotential of Ru-P-Ni(OH)2/NF (denoted as RNPOH/NF) was 98 mV, whereas just 230 mV of overpotential was essential to stimulate alkaline OER at the current density of 20 mA cm-2. Specifically, as a bifunctional electrocatalyst towards overall water splitting, RNPOH/NF deserves cell voltages of 1.7/1.92 V and 1.75/1.94 V, respectively, to activate current densities of 50/100 mA cm-2 in alkaline water/seawater systems, together with a good durability of 12 h. This work contributes insights to the development of bifunctional electrocatalysts for overall water/seawater splitting.

15.
Food Chem ; 459: 140379, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38991437

RESUMO

Precisely detecting organophosphorus pesticides (OPs) is paramount in upholding human safety and environmental preservation, especially in food safety. Herein, an electrochemical acetylcholinesterase (AChE) sensing platform entrapped in chitosan (Chit) on the glassy carbon electrodes (GCEs) decorated with Pt/MoS2/Ti3C2 MXene (Pt/MoS2/TM) was constructed for the detection of chlorpyrifos. It is worth noting that Pt/MoS2/TM possesses good biocompatibility, remarkable electrical conductivity, environmental stability and large specific surface area. Besides, the heterostructure formed by the composite of TM and MoS2 improves the conductivity and maintains the original structure, which is conducive to improving the electrochemical property. The coordination effect between the individual components enables the even distribution of functional components and enhances the electrochemical performance of the biosensor (AChE-Chit/Pt/MoS2/TM). Under optimal efficiency and sensitivity, the AChE-Chit/Pt/MoS2/TM/GCE sensing platform exerts comparable analytical performance and a wide concentration range of chlorpyrifos from 10-12 to 10-6 M as well as a low limit of detection (4.71 × 10-13 M). Furthermore, the biosensor is utilized to detect OPs concerning three kinds of fruits and vegetables with good feasibility and recoveries (94.81% to 104.0%). This work would provide a new scheme to develop high-sensitivity sensors based on the two-dimensional nanosheet/laminar hybrid structure for practical applications in environmental monitoring and agricultural product detection.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Molibdênio , Praguicidas , Platina , Praguicidas/análise , Praguicidas/química , Técnicas Eletroquímicas/instrumentação , Platina/química , Técnicas Biossensoriais/instrumentação , Molibdênio/química , Titânio/química , Acetilcolinesterase/química , Dissulfetos/química , Compostos Organofosforados/química , Compostos Organofosforados/análise , Contaminação de Alimentos/análise , Limite de Detecção , Clorpirifos/análise , Clorpirifos/química , Nanoestruturas/química , Eletrodos
16.
Proc Natl Acad Sci U S A ; 107(7): 2807-12, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20133614

RESUMO

Although the cultural and nutritive importance of the turkey (Meleagris gallopavo) to precontact Native Americans and contemporary people worldwide is clear, little is known about the domestication of this bird compared to other domesticates. Mitochondrial DNA analysis of 149 turkey bones and 29 coprolites from 38 archaeological sites (200 BC-AD 1800) reveals a unique domesticated breed in the precontact Southwestern United States. Phylogeographic analyses indicate that this domestic breed originated from outside the region, but rules out the South Mexican domestic turkey (Meleagris gallopavo gallopavo) as a progenitor. A strong genetic bottleneck within the Southwest turkeys also reflects intensive human selection and breeding. This study points to at least two occurrences of turkey domestication in precontact North America and illuminates the intensity and sophistication of New World animal breeding practices.


Assuntos
Animais Domésticos/genética , Cruzamento/métodos , DNA Mitocondrial/genética , Fósseis , Filogenia , Perus/genética , Animais , Sequência de Bases , Osso e Ossos/química , Análise por Conglomerados , Primers do DNA/genética , Demografia , Fezes/química , Efeito Fundador , Geografia , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Sudoeste dos Estados Unidos , Especificidade da Espécie
17.
J Colloid Interface Sci ; 652(Pt B): 1803-1811, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37683408

RESUMO

Regulating the electrocatalytic hydrogen evolution reaction (HER) performance through defect engineering of the surface of the catalysts is an effective pathway. Herein, cobalt-molybdenum phosphide (CoMoP) nanosheets wrapped molybdenum oxide (MoO3) core-shell nanorods (MoO3@CoMoP), as alkaline electrocatalysts with ligand-derived N-doped carbon hybrid and oxygen-vacancies, were synthesized via solvothermal approaches and followed by phosphorization. As expected, the MoO3@MoCoP affords efficient HER with a low overpotential (η) of 84.2 ± 0.4 mV at 10 mA cm-2. After phosphorization, not only the MoCoP active species are incorporated into the catalyst, but also the defects sites are achieved. Impressively, the metal-ligand-derived MoCoP are distributed uniformly in the N-doped carbon hybrid matrix, exhibiting well-exposed active sites. Benefiting from the synergy effect of MoCoP active species and oxygen-vacancy, the MoO3@MoCoP showed increased conductivity and stability, which can deliver a current density of 10 mA cm-2 over 40 h. MoO3@MoCoP exhibits an optimal electronic structure on the surface by charge redistribution at the interface, thereby optimizing the hydrogen adsorption energy and accelerating the hydrogen evolution kinetics. This work paves the way for the design of transition metal electrocatalysts with desirable properties through a promising strategy in the field of energy conversion.

18.
J Colloid Interface Sci ; 624: 1-13, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35660878

RESUMO

Cellulose acetate membrane (CAM) has become one of the most widely used membrane materials by virtue of stability and hydrophilicity. In this work, to achieve the aim of selective recognition and separation of drug molecule shikimic acid (SA), an effective recognition tactics was proposed by combining boron affinity technology with surface imprinting strategy based on cellulose acetate membrane with low price and biocompatibility. The supporting CAM material was prepared through the phase inversion technique by continuous adjustment of different factors including solvent type and kinds of pore-forming agents, and the optimal CAM with multistage structure and highly porosity was applied for the imprinting of SA. Then the imprinted polymer membrane (MIPs-CAM) was developed via boron affinity surface imprinting polymerization. Various methods (FT-IR, UV-vis, SEM, XPS, AFM and TGA) were used to characterize the structure, morphology, elemental composition, surface roughness and thermal property of the obtained membrane. The as-prepared MIPs-CAM showed homogeneous and abundant imprinted layer, good thermal stability. The batch adsorption results showed that the MIPs-CAM had fast adsorption kinetics, specific recognition ability, and the adsorption capacity could obtain 63.598 mg g-1, which was two times higher than that of non-imprinted membrane (NIPs-CAM). The adsorption isotherms conformed to the Langmuir isotherm and the adsorption processes were spontaneous and endothermic. Additionally, the adsorption capacity of MIPs-CAM still reached 85% of the initial result after five cycles. The experimental results revealed that the molecularly imprinted membrane possessed the advantages of high selectivity and easy recovery compared with the traditional molecular imprinted polymers for SA separation. These results indicate that boron affinity MIPs-CAM with high performance will provide a promising platform for the separation and purification of other cis-diol drug molecules from environmental resources.


Assuntos
Impressão Molecular , Polímeros , Adsorção , Boro , Impressão Molecular/métodos , Polimerização , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Sci Total Environ ; 830: 154765, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35337883

RESUMO

Global effective treatment of phosphorus crisis and toxic waste sludge in one way is urgently needed but still insufficient due to single function, environmental damage, and complicated fabrication process. Herein, we proposed a facile, low-cost, and sustainable strategy to fabricate NiAl layered double oxides/nickel-containing sludge (LDOs/NCS) adsorbent using toxic NCS as raw material via two-step method including hydrothermal process and calcination. The as-designed hierarchical porous adsorbent with large specific surface area and pore volume exhibited excellent adsorption properties towards phosphate. Langmuir adsorption model exhibited the best fit to the experimental data, which illustrated that the adsorption process was dominated by monolayer adsorption. Moreover, even in various double anions systems or in a wide pH range environment (2-12), the as-designed LDOs/NCS still maintained relatively stable adsorption capacity. A possible adsorption mechanism involving surface complexation and electrostatic interactions was investigated. Besides, the LDOs/NCS also displayed admirable durability and reusability. Therefore, this waste-control-waste strategy not only simultaneously addresses phosphorus crisis treatment and toxic NCS management, but also could be potentially extended towards rational design of other metals-containing sludge derived functional materials.


Assuntos
Esgotos , Poluentes Químicos da Água , Adsorção , Substâncias Perigosas , Cinética , Níquel , Óxidos , Fosfatos , Fósforo , Porosidade , Poluentes Químicos da Água/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-35639583

RESUMO

Electrospun micro-/nanofibers with tailor-made specific binding sites are extremely popular due to their tremendous potential in separation applications. In this work, teamed boronate affinity (TBA)-functionalized molecularly imprinted hollow carbon electrospun nanofibers (MI-HCESNFs) derived from ZIF-8/PAN fibers with selective binding sites toward shikimic acid (SA) are presented. Each ingredient used in this strategy plays its own part: HCESNFs with excellent structural characteristics as the highly porous electrospun substrate, KH560 as the grafting material for the follow-up polyethyleneimine (PEI) modification, PEI as the dendritic platform to approach more boronic acid owing to its long chain with abundant amino groups, and TBA molecular group as the functional monomer to specifically bind with SA under the neutral condition. Benefiting from the porous structure, the high density of boronic acid, and the highly accessible imprinted sites on the surface, MI-HCESNFs show strong affinity and selectivity to the SA molecules. The adsorption capacity of MI-HCESNFs can reach 127.8 mg g-1, which is 3.1 times larger than that of the non-imprinted material. Besides, MI-HCESNFs are stable when treated with continuous ultrasonication and can be recycled eight times with a slight loss of 8.615% on the adsorption quantity. This work presents a new strategy to prepare boronate affinity adsorbents based on the electrospinning technique for the capture of SA and also proposes a path for the integration of molecularly imprinted polymers and electrospinning.

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