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1.
J Am Chem Soc ; 146(4): 2798-2804, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38145451

RESUMO

The combination of the chiral concept and inorganic nanostructures holds great potential for significantly impacting catalytic processes and products. However, the synthesis of inorganic nanomaterials with engineered chiroptical activity and identical structure and size presents a substantial challenge, impeding exploration of the relationship between chirality (optical activity) and catalytic efficiency. Here, we present a facile wet-chemical synthesis for achieving intrinsic and tunable chiroptical activity within colloidal copper oxide nanostructures. These nanostructures exhibit strong spin-polarization selectivity compared with their achiral counterparts. More importantly, the ability to engineer chiroptical activity within the same type of chiral nanostructures allows for the manipulation of spin-dependent catalysis, facilitating a study of the connection between the chiroptical magnitude (asymmetric factor) and catalytic performance in inorganic nanostructures. Specifically, using these materials as model catalysts in a proof-of-concept catalytic reaction, we reveal a linear correlation between the asymmetric factor of chiral nanomaterials and the efficiency of the catalytic reaction. This work paves the way for the development of chiral inorganic nanosystems and their application in catalysis through chiroptical engineering.

2.
Nano Lett ; 23(10): 4384-4389, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37162145

RESUMO

Circularly polarized luminescence (CPL) is well-studied in molecular systems but has been rarely reported in pure inorganic nanoscale crystals. Herein, we develop a family of pure inorganic rare-earth nanowires with robust and color-tunable CPL emissions. The chiral rare earth nanowires possess intrinsic atomic chirality with controlled handedness that is guided by the enantiomers with molecular chirality in the synthesis. By varying luminescent ions incorporated in the crystal lattice, color-tunable CPL can be achieved and is thermally robust, preserving emission over 300 °C, distinct from existing CPL-active materials. Moreover, as a proof of concept, we demonstrate that the synthesized nanostructures can be easily dispersed in a polymer matrix to enable transparent and flexible CPL films. This study opens up a promising avenue to design robust and tunable CPL materials helpful to the understanding of inorganic chiral information and capable of further applications in novel optoelectronic devices.

3.
Angew Chem Int Ed Engl ; : e202411871, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054405

RESUMO

Advancing catalyst design is pivotal for the enhancement of photocatalytic processes in renewable energy conversion. The incorporation of structural chirality into conventional inorganic solar hydrogen nanocatalysts promises a significant transformation in catalysis, a feature absent in this field. Here we unveil the unexplored potential of geometric chirality by creating a chiral composite that integrates geometric chiral Au nanoparticles (NPs) with two-dimensional C3N4 nanosheets, significantly boosting photocatalytic H2 evolution beyond the achiral counterparts. The superior performance is driven by the geometric chirality of Au NPs, which facilitates efficient charge carrier separation through the favorable C3N4-chiral Au NP interface and chiral induced spin polarization, and exploits high-activity facets within the concave surfaces of chiral Au NPs. The resulting synergistic effect leads to a remarkable increase in photocatalytic H2 evolution, with an apparent quantum yield of 44.64% at 400 nm. Furthermore, we explore the selective polarized photo-induced carrier separation behavior, revealing a distinct chiral-dependent photocatalytic HER performance. Our work advances the design and utilization of chiral inorganic nanostructures for superior performance in energy conversion processes.

4.
J Am Chem Soc ; 145(13): 7495-7503, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36952630

RESUMO

Understanding and controlling chirality in inorganic crystalline materials at the nanoscale is crucial in elucidating fundamental chirality-dependent physical and chemical processes as well as advancing new technological prospects, but significant challenges remain due to the lack of material control. Here, we have developed a facile and general bottom-up synthetic strategy for achieving chiral plasmonic Au nanostructures, including nanocubes and nanorods with fine chirality control. The underlying chiral mechanism enabled by the chiral boundary morphology is substantiated by theoretical modeling and finite element method (FEM) simulation. Because of the robustness of induced handedness and their small size, these as-synthesized chiral nanostructures can be further employed as building blocks toward the formation of complex chiral nanostructures. We have demonstrated a new class of chiral hybrid metal-semiconductor nanostructures that can allow integration of chirality with other properties and functionalities. All of these together have paved the way to engineer nanoscale inorganic chirality and thus study various emerging chirality-entangled effects with practical technological applications.

5.
Angew Chem Int Ed Engl ; 61(24): e202112400, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34936187

RESUMO

Inorganic chiral hybrid nanostructures that embed chirality within distinct material compositions can create novel chiral properties and functionalities absent from achiral nanostructures; however, they remain largely unexplored. We report, for the first time, a class of chiral plasmonic metal-semiconductor core-shell nanostructures that employ structurally chiral nanoparticles as chirality inducing templates to grow functional shell materials, which allowed us to independently control material parameters such as core geometry and shell thickness, as well as handedness of the system. We experimentally and theoretically achieved enhanced and tunable chiroptical activity of the heterostructures as a result of the core-shell strong coupling effect. As a proof-of-concept demonstration, we demonstrate that the chiral hybrid nanostructures can drive chirality-dependent photocatalytic hydrogen generation under circularly polarized light. This study enables rational design and functionalization of chiral hybrid nanomaterials towards enhanced chiral light-matter interactions and chiral device applications.

6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(5): 680-684, 2020 Sep.
Artigo em Zh | MEDLINE | ID: mdl-32975084

RESUMO

OBJECTIVE: To investigate the dairy product intake during pregnancy in Southwest China and to explore its relationship with neonatal birth body mass. METHODS: A prospective study was conducted to select healthy singleton pregnant women at 8-14 weeks of gestation in a maternal and fetal health care institution in Chengdu City. Dairy product consumption during the first, second, third trimester of pregnancy were collected by 24-hour dietary recalls at 8-14 weeks, 24-28 weeks and 32-36 weeks of pregnancy, respectively, and the total milk intake and milk consumption rate were calculated. According to the dietary guidelines for Chinese pregnant women (2016), the recommended amount of milk (300 g/d) was used as the standard to calculate the compliance rate. The respondents were divided into three groups: no dairy consumption group, insufficient dairy consumption group and suitable dairy consumption group. The gestational age at delivery and neonatal birth body mass were collected by the hospital information system. Logistic regression model was used to analyze the association between milk intake during pregnancy and neonatal birth body mass. RESULTS: A total of 962 pregnant women were included. The average milk intake in the first, second and third trimester of pregnancy were 125.0 (0, 236.1) g/d, 208.3 (0, 284.7) g/d and 250.0 (150.0, 416.7) g/d, respectively, with the compliance rates of 12.6%, 33.2% and 48.4%, respectively. The average neonatal birth body mass was (3 225.0±399.8) g. The incidence of small for gestational age (SGA) and large for gestational age (LGA) was 8.3% and 3.9%, respectively. Compared with no dairy consumption group in the second trimester of pregnancy, the risk of SGA was lower in suitable dairy consumption group (odds ratio (OR)=0.786, 95% confidence interval (CI): 0.385-0.976). Compared with no dairy consumption group in the third trimester of pregnancy, the risk of SGA was lower in insufficient dairy consumption group and suitable dairy consumption group (OR=0.672, 95%CI: 0.477-0.821 and OR=0.497, 95%CI: 0.116-0.807, respectively). No association was observed between milk intake in the first trimester and neonatal birth body mass, and milk intake in the second and third trimester of pregnancy was not associated with the risk of LGA. CONCLUSION: Insufficient milk intake of pregnant women is a significant problem in southwest China and needs to be improved. Milk intake during pregnancy is associated with neonatal birth body mass, and increased milk intake in the second and third trimester of pregnancy may reduce the risk of SGA.


Assuntos
Peso ao Nascer , Registros de Dieta , Recém-Nascido Pequeno para a Idade Gestacional , Parto , China , Feminino , Humanos , Recém-Nascido , Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos
7.
Appl Opt ; 58(26): 6996-7005, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503973

RESUMO

The thermal control system based on a combination of passive and active methods for a compact aerial camera used in the unmanned aerial vehicle system is studied. Integrated analysis and an experimental method are developed to ensure both low-power limit and high image quality of the camera. For rapid estimation of thermal behavior, we develop a thermal mathematic model based on a thermal network method that also offers an initial design reference for the active control system; then we develop a more complex integrated analysis method to analyze and optimize the thermal system, which allows us to get performance insights such as internal temperature gradient and airflow of the compact system. We also focus on analyzing the optical surface errors under thermal disturbance. Comparisons of interferometer test records and thermal-elastic simulation results are presented, and this comparison shows that the integrated optomechanical analysis method contributes to the success of optomechanical system design by ensuring thermal disturbance will not deform the optical surfaces beyond allowable limits. Finally, the design method is verified through a thermo-optic experiment.

8.
J Am Chem Soc ; 140(29): 9095-9098, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-29986582

RESUMO

Colloidal binary supracrystals (SCs) possessing tunable and ordered assembly of two different types of functional nanoparticles (NPs) represent a unique class of artificial materials for both fundamental study and technological applications, but related study has been limited due to substantial challenges in materials growth. Here we report the controlled growth of colloidal binary SCs consisting of Au and Fe3O4 NPs via an oil-in-water emulsion process. The size, stoichiometry, and lattice structure of the SCs can be broadly tuned by the growth parameters. Furthermore, our growth method is general and applicable to other NP building blocks to achieve various functional binary SCs. These as-grown free-standing binary SCs should therefore enable new test beds for exploring different nanoscale interactions ranging from the formation and stability of nanoscale binary phase to the emerging magneto-plasmonic coupling physics.

9.
J Am Chem Soc ; 139(17): 6070-6073, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28414901

RESUMO

Chiral organizations ubiquitously exist in biomaterials via hierarchical assembly of chiral molecules, but assembly of chiral inorganic nanocrystals (NCs) has been lacking. Recent development of cinnabar HgS NCs that can possess precisely engineered chirality originating from both atomic lattice and morphology offers an emerging class of inorganic building blocks to explore their hierarchical assembly. Two different forms of suprastructures, collinear chains and propellers, have been achieved with various chiral HgS NC building blocks via distinct assembly mechanisms. The chiroptical responses of suprastructures are further evaluated both experimentally and theoretically, and are found to uniquely depend on intrinsic chirality of building blocks and their coupling. Our study therefore opens up a gateway to new assembled inorganic suprastructures with desired chiroptical response for wide-ranging functionalities and applications by bottom-up modular approach.

11.
Small ; 11(32): 3909-15, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25939740

RESUMO

Zinc sulfide nanosheet-based hybrid superlattices with tunable periodicities and rod-like or tubular morphologies are constructed by the spontaneous assembly of nanosheets as they grow in amine solution. The as-prepared architectures can be used as an enhanced electrode for photocurrent response and converted to other functional materials.

12.
Adv Mater ; 36(3): e2309033, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944554

RESUMO

Chirality introduces a new dimension of functionality to materials, unlocking new possibilities across various fields. When integrated with plasmonic hybrid nanostructures, this attribute synergizes with plasmonic and other functionalities, resulting in unprecedented chiroptical materials that push the boundaries of the system's capabilities. Recent advancements have illuminated the remarkable chiral light-matter interactions within chiral plasmonic hybrid nanomaterials, allowing for the harnessing of their tunable optical activity and hybrid components. These advancements have led to applications in areas such as chiral sensing, catalysis, and spin optics. Despite these promising developments, there remains a need for a comprehensive synthesis of the current state-of-the-art knowledge, as well as a thorough understanding of the construction techniques and practical applications in this field. This review begins with an exploration of the origins of plasmonic chirality and an overview of the latest advancements in the synthesis of chiral plasmonic hybrid nanostructures. Furthermore, representative emerging categories of hybrid nanomaterials are classified and summarized, elucidating their versatile applications. Finally, the review engages with the fundamental challenges associated with chiral plasmonic hybrid nanostructures and offer insights into the future prospects of this advanced field.

13.
Curr Med Sci ; 44(1): 71-80, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38289530

RESUMO

Cancer patients are at high risk of malnutrition, which can lead to adverse health outcomes such as prolonged hospitalization, increased complications, and increased mortality. Accurate and timely nutritional assessment plays a critical role in effectively managing malnutrition in these patients. However, while many tools exist to assess malnutrition, there is no universally accepted standard. Although different tools have their own strengths and limitations, there is a lack of narrative reviews on nutritional assessment tools for cancer patients. To address this knowledge gap, we conducted a non-systematic literature search using PubMed, Embase, Web of Science, and the Cochrane Library from their inception until May 2023. A total of 90 studies met our selection criteria and were included in our narrative review. We evaluated the applications, strengths, and limitations of 4 commonly used nutritional assessment tools for cancer patients: the Subjective Global Assessment (SGA), Patient-Generated Subjective Global Assessment (PG-SGA), Mini Nutritional Assessment (MNA), and Global Leadership Initiative on Malnutrition (GLIM). Our findings revealed that malnutrition was associated with adverse health outcomes. Each of these 4 tools has its applications, strengths, and limitations. Our findings provide medical staff with a foundation for choosing the optimal tool to rapidly and accurately assess malnutrition in cancer patients. It is essential for medical staff to be familiar with these common tools to ensure effective nutritional management of cancer patients.


Assuntos
Desnutrição , Neoplasias , Avaliação Nutricional , Estado Nutricional , Humanos , Neoplasias/complicações , Desnutrição/diagnóstico
14.
J Am Chem Soc ; 135(18): 6834-7, 2013 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23611283

RESUMO

Biomacromolecules such as proteins, although extremely complex in microstructure, can crystallize into macro-sized crystals after self-adjusting their shapes, based on which the structure of biology is built. Inorganic nanowires/nanoribbons with a similar one-dimensional topology but much simpler structures can hardly be as flexible as macromolecules when constructing superlattice structures because of their inherent rigidity. Here we report the synthesis of crystalline indium sulfide nanoribbon-based nanocoils that are formed by spontaneous self-coiling of ultrathin nanoribbons. The nanostructures are flexible and appear as relatively random coils because of their ultrathin ribbon structures (~0.9 nm in thickness) with high aspect ratios. Moreover, the nanocoils can self-adjust their shapes and assemble into two-dimensional superlattices and three-dimensional supercrystals in solution. The ultrathin nanocoils are expected to bring new insights into the use of flexible nanocrystals as building blocks for constructing superstructures.


Assuntos
Nanoestruturas/química , Cristalização , Tamanho da Partícula , Propriedades de Superfície
15.
Inorg Chem ; 52(16): 9449-55, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23905515

RESUMO

We report the synthesis of a novel hierarchical MnO2/SnO2 heterostructures via a hydrothermal method. Secondary SnO2 nanostructure grows epitaxially on the surface of MnO2 backbones without any surfactant, which relies on the minimization of surface energy and interfacial lattice mismatch. Detailed investigations reveal that the cover density and morphology of the SnO2 nanostructure can be tailored by changing the experimental parameter. Moreover, we demonstrate a bottom-up method to produce energetic nanocomposites by assembling nanoaluminum (n-Al) and MnO2/SnO2 hierarchical nanostructures into a free-standing MnO2/SnO2/n-Al ternary thermite membrane. This assembled approach can significantly reduce diffusion distances and increase their intimacy between the components. Different thermite mixtures were investigated to evaluate the corresponding activation energies using DSC techniques. The energy performance of the ternary thermite membrane can be manipulated through different components of the MnO2/SnO2 heterostructures. Overall, our work may open a new route for new energetic materials.

16.
Yao Xue Xue Bao ; 48(11): 1677-87, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24475705

RESUMO

Carbon monoxide has been proved to be an important signal molecule in body. Transition metal carbonyl compounds are solidified form of carbon monoxide. Numerous studies have shown that Ruthenium carbonyl carbon monoxide releasing molecules have a strong pharmacological activity. In this paper, five Ruthenium (II) carbonyl CORMs 1-5 were synthesized and their toxicology, tissue distribution and interaction with blood endogenous substances were investigated. The results showed CORMs' IC50 to fibroblasts are ranged from 212.9 to 2089.2 micromol x L(-1). Their oral LD50 to mouse is between 800 to 1600 mg x kg(-1). After repeated administration, CORMs 1 and CORMs 5 haven't shown an obvious influence to rats' liver and kidney function, but caused the injury to liver and kidney cells. The in vivo distribution result revealed the majority of CORMs were distributed in blood, liver and kidney, only a small part of CORMs distributed in lung, heart and spleen. They could scarcely cross the blood-brain barrier and distribute to brain. The non-CO ligands in structure have an obvious relevance to their in vivo absorption and distribution. Interestingly, CORMs could enhance the fluorescence of bovine serum albumin, and this enhancement was in direct proportion with the concentration of CORMs. Under different conditions, interaction of CORMs with glutathione got different type of products, one is Ruthenium (II) tricarbonyl complexes, and Ruthenium (II) dicarbonyl complexes.


Assuntos
Monóxido de Carbono/química , Compostos Organometálicos/síntese química , Rutênio/química , Animais , Monóxido de Carbono/farmacocinética , Monóxido de Carbono/toxicidade , Fibroblastos/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Camundongos , Estrutura Molecular , Compostos Organometálicos/química , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/toxicidade , Ratos , Ratos Wistar , Rutênio/farmacocinética , Rutênio/toxicidade , Distribuição Tecidual
17.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): o189, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23424474

RESUMO

The asymmetric unit of the title compound, C(12)H(16)O(2), contains two independent mol-ecules in which the dihedral angles between the benzene and cyclo-propane rings are 75.9 (3) and 76.3 (3)°. In the crystal, the mol-ecules are connected by O-H⋯O hydrogen bonds into a three dimensional supra-molecular structure.

18.
Mar Pollut Bull ; 186: 114462, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521364

RESUMO

Massive blooms of Nemopilema nomurai have occurred recently across East Asian waters. They are potentially important as zooplankton predators, as well as being competitors for prey with zooplanktivorous fish. Few studies have estimated the predation effects on zooplankton by N. nomurai in situ. To quantify the natural diets and feeding rates and estimate the predation effects, N. nomurai medusae were collected in the northern East China Sea and southern Yellow Sea, one of the principal nursery grounds of this jellyfish, during May 2019. The gut contents indicated that copepods were an important food source for N. nomurai; copepods <1000 µm represented the bulk of total prey intake in number (> 99 %). Linear regression analyses showed that the copepods number in the gut contents was significantly influenced by medusa diameter and prey abundance. Calculations using the above data indicated that one medusa (mean diameter: 26.06 ± 9.73 cm) consumed approximately 5248 ± 2768 of copepods daily. However, even the maximum predation pressure was <0.1 % of the total copepods standing stock daily due to the small diameter and low density/biomass of N. nomurai medusae in May 2019. The data presented here suggested that the predation effects of N. nomurai on copepods were low and might not reduce prey availability to fish with diets consisting mainly of copepods during the early occurrence stage of the N. nomurai population.


Assuntos
Cnidários , Copépodes , Cifozoários , Animais , Comportamento Predatório , Zooplâncton
19.
ACS Nano ; 17(17): 16326-16347, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37540624

RESUMO

Chiral inorganic nanomaterials due to their unique asymmetric nanostructures have gradually demonstrated intriguing chirality-dependent performance in photo(electro)catalytic conversion, such as water splitting. However, understanding the correlation between chiral inorganic characteristics and the photo(electro)catalytic process remains challenging. In this perspective, we first highlight the chirality source of inorganic nanomaterials and briefly introduce photo(electro)catalysis systems. Then, we delve into an in-depth discussion of chiral effects exerted by chiral nanostructures and their photo-electrochemistry properties, while emphasizing the emerging chiral inorganic nanomaterials for photo(electro)catalytic conversion. Finally, the challenges and opportunities of chiral inorganic nanomaterials for photo(electro)catalytic conversion are prospected. This perspective provides a comprehensive overview of chiral inorganic nanomaterials and their potential in photo(electro)catalytic conversion, which is beneficial for further research in this area.

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o381, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22347004

RESUMO

In the title compound, C(16)H(16)N(2)O(6), the dihedral angle between the two pyrrolidine rings is 79.38 (14)°.

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