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1.
Nature ; 612(7938): 83-87, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36289345

RESUMO

Achieving carbon neutrality requires deploying renewable energy at unprecedented speed and scale1,2, yet countries sometimes implement policies that increase costs by restricting the free flow of capital, talent and innovation in favour of localizing benefits such as economic growth, employment and trade surpluses3,4. Here we assess the cost savings from a globalized solar photovoltaic (PV) module supply chain. We develop a two-factor learning model using historical capacity, component and input material price data of solar PV deployment in the United States, Germany and China. We estimate that the globalized PV module market has saved PV installers US$24 (19-31) billion in the United States, US$7 (5-9) billion in Germany and US$36 (26-45) billion in China from 2008 to 2020 compared with a counterfactual scenario in which domestic manufacturers supply an increasing proportion of installed capacities over a ten-year period. Projecting the same scenario forwards from 2020 results in estimated solar module prices that are approximately 20-25 per cent higher in 2030 compared with a future with globalized supply chains. International climate policy benefits from a globalized low-carbon value chain4, and these results point to the need for complementary policies to mitigate welfare distribution effects and potential impacts on technological crowding out.

2.
Plant Cell ; 35(1): 369-389, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36173348

RESUMO

Maize (Zea mays) originated in southern Mexico and has spread over a wide latitudinal range. Maize expansion from tropical to temperate regions has necessitated a reduction of its photoperiod sensitivity. In this study, we cloned a quantitative trait locus (QTL) regulating flowering time in maize and show that the maize ortholog of Arabidopsis thaliana EARLY FLOWERING3, ZmELF3.1, is the causal locus. We demonstrate that ZmELF3.1 and ZmELF3.2 proteins can physically interact with ZmELF4.1/4.2 and ZmLUX1/2, to form evening complex(es; ECs) in the maize circadian clock. Loss-of-function mutants for ZmELF3.1/3.2 and ZmLUX1/2 exhibited delayed flowering under long-day and short-day conditions. We show that EC directly represses the expression of several flowering suppressor genes, such as the CONSTANS, CONSTANS-LIKE, TOC1 (CCT) genes ZmCCT9 and ZmCCT10, ZmCONSTANS-LIKE 3, and the PSEUDORESPONSE REGULATOR (PRR) genes ZmPRR37a and ZmPRR73, thus alleviating their inhibition, allowing florigen gene expression and promoting flowering. Further, we identify two closely linked retrotransposons located in the ZmELF3.1 promoter that regulate the expression levels of ZmELF3.1 and may have been positively selected during postdomestication spread of maize from tropical to temperate regions during the pre-Columbian era. These findings provide insights into circadian clock-mediated regulation of photoperiodic flowering in maize and new targets of genetic improvement for breeding.


Assuntos
Arabidopsis , Zea mays , Zea mays/metabolismo , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/genética , Aclimatação/genética , Fotoperíodo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética
3.
Nano Lett ; 24(30): 9311-9321, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39023921

RESUMO

The doping of perovskites with mixed cations and mixed halides is an effective strategy to optimize phase stability. In this study, we introduce a cubic black phase perovskite CsyFA(1-y)Pb(BrxI(1-x))3 artificial synapse, using phase engineering by adjusting the cesium-bromide content. Low-bromine mixed perovskites are suitable to improve the electric pulse excitation sensitivity and stability of the device. Specifically, the low-bromine and low-cesium mixed perovskite (x = 0.15, y = 0.22) annealed at 373 K allows the device to maintain logic response even after 1000 mechanical flex/flat cycles. The device also shows good thermal stability up to temperatures of 333 K. We have demonstrated reflex-arc behavior with MCMHP synaptic units, capable of making sensory warnings at high frequency. This compositionally engineered, dual-mixed perovskite synaptic device provides significant potential for perceptual soft neurorobotic systems and prostheses.

4.
J Cell Mol Med ; 28(7): e18212, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38516826

RESUMO

SBFI26, an inhibitor of FABP5, has been shown to suppress the proliferation and metastasis of tumour cells. However, the underlying mechanism by which SBFI26 induces ferroptosis in breast cancer cells remains largely unknown. Three breast cancer cell lines were treated with SBFI26 and CCK-8 assessed cytotoxicity. Transcriptome was performed on the Illumina platform and verified by qPCR. Western blot evaluated protein levels. Malondialdehyde (MDA), total superoxide dismutase (T-SOD), Fe, glutathione (GSH) and oxidized glutathione (GSSG) were measured. SBFI26 induced cell death time- and dose-dependent, with a more significant inhibitory effect on MDA-MB-231 cells. Fer-1, GSH and Vitamin C attenuated the effects but not erastin. RNA-Seq analysis revealed that SBFI26 treatment significantly enriched differentially expressed genes related to ferroptosis. Furthermore, SBFI26 increased intracellular MDA, iron ion, and GSSG levels while decreasing T-SOD, total glutathione (T-GSH), and GSH levels.SBFI26 dose-dependently up-regulates the expression of HMOX1 and ALOX12 at both gene and protein levels, promoting ferroptosis. Similarly, it significantly increases the expression of SAT1, ALOX5, ALOX15, ALOXE3 and CHAC1 that, promoting ferroptosis while downregulating the NFE2L2 gene and protein that inhibit ferroptosis. SBFI26 leads to cellular accumulation of fatty acids, which triggers excess ferrous ions and subsequent lipid peroxidation for inducing ferroptosis.


Assuntos
Ferroptose , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Dissulfeto de Glutationa , Ferroptose/genética , Peroxidação de Lipídeos , Glutationa , Ferro , Superóxido Dismutase/genética , Espécies Reativas de Oxigênio , Proteínas de Ligação a Ácido Graxo
5.
J Am Chem Soc ; 146(9): 5952-5963, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38408428

RESUMO

The ability of alkylamines to spontaneously liberate hydride ions is typically restrained, except under specific intramolecular reaction settings. Herein, we demonstrate that this reactivity can be unlocked through simple treatment with formaldehyde in hexafluoroisopropanol (HFIP) solvent, thereby enabling various intermolecular hydride transfer reactions of alkylamines under mild conditions. Besides transformations of small molecules, these reactions enable unique late-stage modification of complex peptides. Mechanistic investigations uncover that the key to these intermolecular hydride transfer processes lies in the accommodating conformation of solvent-mediated macrocyclic transition states, where the aggregates of HFIP molecules act as dexterous proton shuttles. Importantly, negative hyperconjugation between the lone electron pair of nitrogen and the antibonding orbital of amine's α C-H bond plays a critical role in the C-H activation, promoting its hydride liberation.

6.
Glob Chang Biol ; 30(3): e17256, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532549

RESUMO

Denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) are three competing processes of microbial nitrate reduction that determine the degree of ecosystem nitrogen (N) loss versus recycling. However, the global patterns and drivers of relative contributions of these N cycling processes to soil or sediment nitrate reduction remain unknown, limiting our understanding of the global N balance and management. Here, we compiled a global dataset of 1570 observations from a wide range of terrestrial and aquatic ecosystems. We found that denitrification contributed up to 66.1% of total nitrate reduction globally, being significantly greater in estuarine and coastal ecosystems. Anammox and DNRA could account for 12.7% and 21.2% of total nitrate reduction, respectively. The contribution of denitrification to nitrate reduction increased with longitude, while the contribution of anammox and DNRA decreased. The local environmental factors controlling the relative contributions of the three N cycling processes to nitrate reduction included the concentrations of soil organic carbon, ammonium, nitrate, and ferrous iron. Our results underline the dominant role of denitrification over anammox and DNRA in ecosystem nitrate transformation, which is crucial to improving the current global soil N cycle model and achieving sustainable N management.


Assuntos
Compostos de Amônio , Nitratos , Nitratos/análise , Ecossistema , Desnitrificação , Carbono , Solo , Nitrogênio , Oxirredução
7.
Biomacromolecules ; 25(4): 2574-2586, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38525818

RESUMO

Developing biocompatible injectable hydrogels with high mechanical strength and rapid strong tissue adhesion for hemostatic sealing of uncontrolled bleeding remains a prevailing challenge. Herein, we engineer an injectable and photo-cross-linkable hydrogel based on naturally derived gelatin methacrylate (GelMA) and N-hydroxysuccinimide-modified poly(γ-glutamic acid) (γPGA-NHS). The chemically dual-cross-linked hydrogel rapidly forms after UV light irradiation and covalently bonds to the underlying tissue to provide robust adhesion. We demonstrate a significantly improved hemostatic efficacy of the hydrogel using various injury models in rats compared to the commercially available fibrin glue. Notably, the hydrogel can achieve hemostasis in porcine liver and spleen incision, and femoral artery puncture models. Moreover, the hydrogel is used for sutureless repair of the liver defect in a rat model with a significantly suppressed inflammatory response, enhanced angiogenesis, and superior healing efficacy compared to fibrin glue. Together, this study offers a promising bioadhesive for treating severe bleeding and facilitating wound repair.


Assuntos
Hemostáticos , Hidrogéis , Ratos , Animais , Suínos , Hidrogéis/farmacologia , Hidrogéis/química , Adesivo Tecidual de Fibrina , Adesivos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Hemostáticos/farmacologia , Hemorragia/tratamento farmacológico , Cicatrização
8.
J Org Chem ; 89(9): 6263-6273, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38652889

RESUMO

Herein, we presented a practical methodology for the intermolecular aziridination of alkenes, using HOSA as the aminating agent, alongside pyridine or piperidine as the base, within HFIP solvent system. Notably, this approach showcases excellent reactivity, especially with nonactivated alkenes, and facilitates the transformation of various alkenes substrates, including mono-, di-, tri, and tetra-substituted alkenes, into aziridines with moderate to excellent yield. This method presents a promising avenue for synthesizing aziridines from a wide range of alkenes, featuring the benefits of straightforward operation, mild reaction conditions, extensive substrate compatibility, and scalability.

9.
Environ Sci Technol ; 58(12): 5187-5195, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38490225

RESUMO

Clean hydrogen has the potential to serve as an energy carrier and feedstock in decarbonizing energy systems, especially in "hard-to-abate" sectors. Although many countries have implemented policies to promote electrolytic hydrogen development, the impact of these measures on costs of production and greenhouse gas emissions remains unclear. Our study conducts an integrated analysis of provincial levelized costs and life cycle greenhouse gas emissions for all hydrogen production types in China. We find that subsidies are critical to accelerate low carbon electrolytic hydrogen development. Subsidies on renewable-based hydrogen provide cost-effective carbon dioxide equivalent (CO2e) emission reductions. However, subsidies on grid-based hydrogen increase CO2e emissions even compared with coal-based hydrogen because grid electricity in China still relies heavily on coal power and likely will beyond 2030. In fact, CO2e emissions from grid-based hydrogen may increase further if China continues to approve new coal power plants. The levelized costs of renewable energy-based electrolytic hydrogen vary among provinces. Transporting renewable-based hydrogen through pipelines from low- to high-cost production regions reduces the national average levelized cost of renewables-based hydrogen but may increase the risk of hydrogen leakage and the resulting indirect warming effects. Our findings emphasize that policy and economic support for nonfossil electrolytic hydrogen is critical to avoid an increase in CO2e emissions as hydrogen use rises during a clean energy transition.


Assuntos
Gases de Efeito Estufa , Carvão Mineral , Efeito Estufa , Hidrogênio , Centrais Elétricas , Dióxido de Carbono/análise
10.
Crit Care ; 28(1): 225, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978111

RESUMO

BACKGROUND: The precise identification of the underlying causes of infectious diseases, such as severe pneumonia, is essential, and the development of next-generation sequencing (NGS) has enhanced the effectiveness of pathogen detection. However, there is limited information on the systematic assessment of the clinical use of targeted next-generation sequencing (tNGS) in cases of severe pneumonia. METHODS: A retrospective analysis was conducted on 130 patients with severe pneumonia treated in the ICU from June 2022 to June 2023. The consistency of the results of tNGS, metagenomics next-generation sequencing (mNGS), and culture with the clinical diagnosis was evaluated. Additionally, the results for pathogens detected by tNGS were compared with those of culture, mNGS, and quantitative reverse transcription PCR (RT-qPCR). To evaluate the efficacy of monitoring severe pneumonia, five patients with complicated infections were selected for tNGS microbiological surveillance. The tNGS and culture drug sensitisation results were then compared. RESULTS: The tNGS results for the analysis of the 130 patients showed a concordance rate of over 70% with clinical diagnostic results. The detection of pathogenic microorganisms using tNGS was in agreement with the results of culture, mNGS, and RT-qPCR. Furthermore, the tNGS results for pathogens in the five patients monitored for complicated infections of severe pneumonia were consistent with the culture and imaging test results during treatment. The tNGS drug resistance results were in line with the drug sensitivity results in approximately 65% of the cases. CONCLUSIONS: The application of tNGS highlights its promise and significance in assessing the effectiveness of clinical interventions and providing guidance for anti-infection therapies for severe pneumonia.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Pneumonia , Humanos , Estudos Retrospectivos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Pneumonia/diagnóstico , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos
12.
Pediatr Crit Care Med ; 25(5): 425-433, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38353591

RESUMO

OBJECTIVES: To describe the epidemiological characteristics of pediatric sepsis in Southwest China PICUs. DESIGN: A prospective, multicenter, and observational study. SETTING: Twelve PICUs in Southwest China. PATIENTS: The patients admitted to the PICU from April 1, 2022, to March 31, 2023. The age ranged from 28 days to 18 years. All patients met the criteria of severe sepsis or septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 31 PICUs invited to participate, 12 PICUs (capacity of 292 beds) enrolled patients in the study. During the study period, 11,238 children were admitted to the participating PICUs, 367 (3.3%) of whom met the diagnosis of severe sepsis or septic shock. The most prevalent sites of infection were the respiratory system (55%) and the digestive system (15%). The primary treatments administered to these patients included antibiotics (100%), albumin (61.3%), invasive mechanical ventilation (58.7%), glucocorticoids (55.6%), blood products (51%), gammaglobulin (51%), and vasoactive medications (46.6%). Sepsis-related mortality in the PICU was 11.2% (41/367). Nearly half of the sepsis deaths occurred within the first 3 days of PICU admission (22/41, 53.7%). The mortality rate of septic shock (32/167, 19.2%) was significantly higher than that of severe sepsis (9/200, 4.5%; p < 0.001). The outcomes of a multivariate logistic regression analysis suggested that a higher pediatric Sequential Organ Failure Assessment score, and the use of invasive mechanical ventilation and vasoactive medications were independently associated with PICU mortality in children with sepsis. CONCLUSIONS: This report updates the epidemiological data of pediatric sepsis in PICUs in Southwest China. Sepsis is still a life-threatening disease in children.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Sepse , Humanos , Estudos Prospectivos , Pré-Escolar , China/epidemiologia , Criança , Lactente , Masculino , Feminino , Adolescente , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Sepse/epidemiologia , Recém-Nascido , Mortalidade Hospitalar , Choque Séptico/epidemiologia
13.
Mikrochim Acta ; 191(6): 353, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809482

RESUMO

Organic pollutant detection has caused widespread concern regarding due to their potential environmental and human health risks. In this work, a nitrogen-doped titanium dioxide/silver oxide (N-TiO2/Ag2O) composite has been designed as a sensitive photoelectrochemical (PEC) monitoring platform of organic dyes. Sensitive determination relies on the outstanding PEC performance of N-TiO2/Ag2O. The improved PEC performance stems from the effective separation of photocarriers and the extended light response range provided by the narrowing bandgap and a p-n junction with N-TiO2/Ag2O. The N-TiO2/Ag2O electrode exhibits a photocurrent density of up to 2.2 mA/cm2, demonstrating three times increase compared with the photocurrent density observed with the pure TiO2 film. The linear detection range for rhodamine B (RhB), methylene blue (MB), and methyl orange (MO) is 0.2 ng/mL to 10 µg/mL with an ultrasensitive detection limit of 0.2 ng/mL without bias voltage. Due to the outstanding photocurrent density and sensitive response to organic pollutants, the N-TiO2/Ag2O PEC sensor provided a promising analytical method to detect environmental organic dyes.

14.
Sensors (Basel) ; 24(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38203161

RESUMO

Recently, advancements in image sensor technology have paved the way for the proliferation of high-dynamic-range television (HDRTV). Consequently, there has been a surge in demand for the conversion of standard-dynamic-range television (SDRTV) to HDRTV, especially due to the dearth of native HDRTV content. However, since SDRTV often comes with video encoding artifacts, SDRTV to HDRTV conversion often amplifies these encoding artifacts, thereby reducing the visual quality of the output video. To solve this problem, this paper proposes a multi-frame content-aware mapping network (MCMN), aiming to improve the performance of conversion from low-quality SDRTV to high-quality HDRTV. Specifically, we utilize the temporal spatial characteristics of videos to design a content-aware temporal spatial alignment module for the initial alignment of video features. In the feature prior extraction stage, we innovatively propose a hybrid prior extraction module, including cross-temporal priors, local spatial priors, and global spatial prior extraction. Finally, we design a temporal spatial transformation module to generate an improved tone mapping result. From time to space, from local to global, our method makes full use of multi-frame information to perform inverse tone mapping of single-frame images, while it is also able to better repair coding artifacts.

15.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38475167

RESUMO

The fast development of the sensors in the wireless sensor networks (WSN) brings a big challenge of low energy consumption requirements, and Peer-to-peer (P2P) communication becomes the important way to break this bottleneck. However, the interference caused by different sensors sharing the spectrum and the power limitations seriously constrains the improvement of WSN. Therefore, in this paper, we proposed a deep reinforcement learning-based energy consumption optimization for P2P communication in WSN. Specifically, P2P sensors (PUs) are considered agents to share the spectrum of authorized sensors (AUs). An authorized sensor has permission to access specific data or systems, while a P2P sensor directly communicates with other sensors without needing a central server. One involves permission, the other is direct communication between sensors. Each agent can control the power and select the resources to avoid interference. Moreover, we use a double deep Q network (DDQN) algorithm to help the agent learn more detailed features of the interference. Simulation results show that the proposed algorithm can obtain a higher performance than the deep Q network scheme and the traditional algorithm, which can effectively lower the energy consumption for P2P communication in WSN.

16.
Prep Biochem Biotechnol ; 54(7): 859-871, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38149618

RESUMO

Polysaccharides derived from Auricularia auricula exhibit diverse biological activities and hold significant potential for commercial utilization as functional food ingredients. In this investigation, polysaccharides from A. auricula were obtained using six extraction techniques (ammonium oxalate solution extraction, sodium hydroxide solution extraction, hot water extraction, pectinase and cellulase-assisted extraction, ultrasonic-assisted extraction, and microwave-assisted extraction). Subsequently, a comprehensive comparison was conducted to evaluate their physicochemical properties and biological functionalities. The ammonium oxalate solution extraction method yielded a higher extraction rate (11.76%) and polysaccharide content (84.12%), as well as a higher uronic acid content (10.13%). Although the six Auricularia polysaccharides had different molecular weight distributions, monosaccharide molar ratios, similar monosaccharide compositions, and characteristic functional groups of polysaccharides, they exhibited different surface morphology. In vitro assays showed that polysaccharides extracted by ammonium oxalate solution possessed good scavenging ability against DPPH free radical, hydroxyl free radical and superoxide anion free radical as well as reduction power of iron ion. At the same time, both polysaccharides extracted by ammonium oxalate solution and sodium hydroxide solution promoted NO production in mouse macrophages along with the secretion of cytokines TNF-α, IL-1ß, and IL-6. These results indicated significant differences in the structure and characteristics among Auricularia polysaccharides prepared by various extraction methods, which may be related to the variety or origin of A. auricula; furthermore, their bioactivities varied accordingly in vitro assays where the ammonium oxalate solution extraction method was found more beneficial for obtaining high-quality bioactive Auricularia polysaccharides.


Assuntos
Auricularia , Camundongos , Animais , Auricularia/química , Células RAW 264.7 , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/isolamento & purificação , Polissacarídeos Fúngicos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Polissacarídeos/química , Peso Molecular , Óxido Nítrico , Fracionamento Químico/métodos , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo
17.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2871-2881, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-39041146

RESUMO

To investigate the effects of different ratios of organic and chemical fertilizers on the yield and quality of Epimedium pubescens,so as to provide a scientific basis for the fertilization of high-yield and high-quality E. pubescens cultivation. In this experiment,a field plot test was conducted,and CK(without fertilizer) was set as the control group,with five treatment groups with different ratios of organic fertilizers and chemical fertilizers set up,namely OF0(100% chemical fertilizers),OF25(25% organic fertilizers),OF50(50% organic fertilizers),OF75(75% organic fertilizers),and OF100(100% organic fertilizers). The effects of different fertilization patterns on the agronomic traits,yield,effective component content,nutrient accumulation,and soil physicochemical properties of E. pubescens were determined,and the yield and quality of the medicinal herb were comprehensively evaluated by using the CRITIC weights method. It was found that the herb yield of each treatment group was significantly increased compared with the CK group,although the yield of the groups with both organic fertilizer and chemical fertilizer was slightly lower than that of OF0. However,there was no significant difference,which indicated that the organic fertilizer combined with chemical fertilizer could ensure the herb yield. With the increase in organic fertilizer ratios,the medicinal components epimedin A,epimedin B,and epimedin C showed a tendency of first increasing and then decreasing,with the highest content in the OF25,while icariin showed a rising trend,with the best in the OF100. However,overall,the total flavonol glycosides ABCI accumulated the most in the OF25. The results of the CRITIC method showed that the top three fertilization treatments in terms of the comprehensive scores of the medicinal herb were OF25,OF50,and OF75. Organic fertilizer combined with chemical fertilizer is conducive to improving the soil's fertilizer holding and supply capacity,and the soil indexes are optimal in OF100. The soil enzyme activity is the highest in OF75. Meanwhile,organic fertilizer combined with chemical fertilizer can help the plant's uptake and accumulation of nutrients,and OF25 shows the most obvious effect.By comprehensively considering the influence of different ratios of organic and chemical fertilizers on the yield,effective component content,nutrient accumulation,and other indexes of E. pubescens,it is recommended that a 25% ratio(7 500 kg·hm~(-2)) of organic fertilizers and chemical fertilizers should be used in E. pubescens production in the first year,so as to promote the E. pubescens industry to increase yield and improve quality.


Assuntos
Epimedium , Fertilizantes , Fertilizantes/análise , Epimedium/química , Epimedium/crescimento & desenvolvimento , Solo/química , Nitrogênio/metabolismo , Nitrogênio/análise , Controle de Qualidade
18.
Angew Chem Int Ed Engl ; : e202410525, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041715

RESUMO

Directional electron flow in the photocatalyst enables efficient charge separation, which is essential for efficient photocatalysis of H2 production. Here, we report a novel class of tetracationic cyclophanes (7) incorporating bipyridine Pt(II) and selenoviologen. X-ray single-crystal structures reveal that 7 not only fixes the distances and spatial positions between its individual units but also exhibits a box-like rigid electron-deficient cavity. Moreover, host-guest recognition phenomena are observed between 7 and ferrocene, forming host-guest complexes with a 1:1 stoichiometry in MeCN. 7 exhibits good redox properties, narrow energy gaps, and strong absorption in the visible range (370-500 nm) due to containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that 7 has stabilized dicationic biradical, efficient charge separation, and facilitates directional electron flow to achieve efficient electron transfer due to the formation of rigid cyclophane and electronic architecture. Then, 7 is applied to visible-light-driven hydrogen evolution with high hydrogen production (132 µmol), generation rate (11 µmol/h), turnover number (221), and apparent quantum yield (1.7%), which provides a simplified and efficient photocatalytic strategy for solar energy conversion.

19.
Angew Chem Int Ed Engl ; 63(6): e202314454, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38009676

RESUMO

Quasiperiodic patterns and crystals-having long range order without translational symmetry-have fascinated researchers since their discovery. In this study, we report on new p-terphenyl-based T-shaped facial polyphiles with two alkyl end chains and a glycerol-based hydrogen-bonded side group that self-assemble into an aperiodic columnar liquid quasicrystal with 12-fold symmetry and its periodic liquid-crystalline approximants with complex superstructures. All represent honeycombs formed by the self-assembly of the p-terphenyls, dividing space into prismatic cells with polygonal cross-sections. In the perspective of tiling patterns, the presence of unique trapezoidal tiles, consisting of three rigid sides formed by the p-terphenyls and one shorter, incommensurate, and adjustable side by the alkyl end chains, plays a crucial role for these phases. A delicate temperature-dependent balance between conformational, entropic and space-filling effects determines the role of the alkyl chains, either as network nodes or trapezoid walls, thus resulting in the order-disorder transitions associated with emergence of quasiperiodicity. In-depth analysis suggests a change from a quasiperiodic tiling involving trapezoids to a modified one with a contribution of trapezoid pair fusion. This work paves the way for understanding quasiperiodicity emergence and develops fundamental concepts for its generation by chemical design of non-spherical molecules, aggregates, and frameworks based on dynamic reticular chemistry.

20.
Angew Chem Int Ed Engl ; 63(2): e202312465, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37997539

RESUMO

Herein, we report that bulky alkylphosphines such as PtBu3 can switch the roles from actor to spectator ligands to promote the FeCl2 -catalyzed N-amidation reaction of arylamines with dioxazolones, giving hydrazides in high efficiency and chemoselectivity. Mechanistic studies indicated that the phosphine ligands could facilitate the decarboxylation of dioxazolones on the Fe center, and the hydrogen bonding interactions between the arylamines and the ligands on Fe nitrenoid intermediates might play a role in modulating the delicate interplay between the phosphine ligand, arylamine, and acyl nitrene N, favoring N-N coupling over N-P coupling. The new ligand-promoted N-amidation protocols offer a convenient way to access various challenging triazane compounds via double or sequential N-amidation of primary arylamines.

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