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1.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1485-1493, 2024 Mar.
Article in Chinese | MEDLINE | ID: mdl-38621932

ABSTRACT

Chuanxiong Rhizoma is a well-known Sichuan-specific herbal medicine. Its original plant, Ligusticum chuanxiong, has been cultivated asexually for a long time. L. chuanxiong has sexual reproductive disorders, which restricts its germplasm innovation. However, there is little research on the reproductive system of L. chuanxiong. This study is based on a comparative anatomical research approach, using morphological dissection, paraffin sectioning, staining and compression, and combined with scanning electron microscopy technology, to observe and compare the flowers, fruits, and seeds at various stages of reproductive growth of L. chuanxiong and its wild relative L. sinense. The results showed that the meiosis of pollen mother cells is abnormal in L. chuanxiong anthers, and the size and number of microspores are uneven and inconsistent in the tetrad stage. tapetum cells are not completely degenerated during anther development. During the pollen ripening stage, there are fine cracks in the anther wall, while most anthers could not release pollen normally. The surface of mature pollen grains is concave and partially deformed, and the pollens are all inactive and cannot germinate in vitro. The starch, polysaccharides, and lipids in the pollen were insufficient. The filaments of L. chuanxiong are short at the flowering stage and recurved downward. Double-hanging fruits were observed in the fruiting stage, being wrinkled; with shriveled seeds. Compared with L. sinense at the same stage, the anthers of L. sinense developed normally, and the pollen grains are vigorous and can germinate in vitro. The double-hanging fruits of L. sinense are full and normal; at the flowering period, the filaments are long and erect, significantly higher than the stigma. Mature blastocysts are visible in the ovary of both L. chuanxiong and L. sinense, and there is no significant difference in stigmas. The conclusion is that during the development of L. chuanxiong stamens, the meiosis of pollen mother cells is abnormal, and tetrad, tapetum, filament and other pollen structures develop abnormally. L. chuanxiong has the characteristic of male infertility, which is an important reason for its sexual reproductive disorders.


Subject(s)
Ligusticum , Reproduction , Pollen , Flowers , Polysaccharides
2.
Small ; : e2400662, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38534137

ABSTRACT

Developing high-performance electrocatalysts for alkaline hydrogen evolution reaction (HER) is crucial for producing green hydrogen, yet it remains challenging due to the sluggish kinetics in alkaline environments. Pt is located near the peak of HER volcano plot, owing to its exceptional performance in hydrogen adsorption and desorption, and Rh plays an important role in H2O dissociation. Lanthanides (Ln) are commonly used to modulate the electronic structure of materials and further influence the adsorption/desorption of reactants, intermediates, and products, and noble metal-Ln alloys are recognized as effective platforms where Ln elements regulate the catalytic properties of noble metals. Here Pt1.5Rh1.5Tm alloy is synthesized using the sodium vapor reduction method. This alloy demonstrates superior catalytic activity, being 4.4 and 6.6 times more effective than Pt/C and Rh/C, respectively. Density Functional Theory (DFT) calculations reveal that the upshift of d-band center and the charge transfer induced by alloying promote adsorption and dissociation of H2O, making Pt1.5Rh1.5Tm alloy more favorable for the alkaline HER reaction, both kinetically and thermodynamically.

3.
J Am Chem Soc ; 146(13): 9012-9025, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38516778

ABSTRACT

The development of efficient and stable catalysts for hydrogen production from electrolytic water in a wide pH range is of great significance in alleviating the energy crisis. Herein, Pt nanoparticles (NPs) anchored on the vacancy of high entropy rare earth oxides (HEREOs) were prepared for the first time for highly efficient hydrogen production by water electrolysis. The prepared Pt-(LaCeSmYErGdYb)O showed excellent electrochemical performances, which require only 12, 57, and 77 mV to achieve a current density of 100 mA cm-2 in 0.5 M H2SO4, 1.0 M KOH, and 1.0 M PBS environments, respectively. In addition, Pt-(LaCeSmYErGdYb)O has successfully worked at 400 mA cm-2 @ 60 °C for 100 h in 0.5 M H2SO4, presenting the high mass activity of 37.7 A mg-1Pt and turnover frequency (TOF) value of 38.2 s-1 @ 12 mV, which is far superior to the recently reported hydrogen evolution reaction (HER) catalysts. Density functional theory (DFT) calculations have revealed that the interactions between Pt and HEREO have optimized the electronic structures for electron transfer and the binding strength of intermediates. This further leads to optimized proton binding and water dissociation, supporting the highly efficient and robust HER performances in different environments. This work provides a new idea for the design of efficient RE-based electrocatalysts.

4.
Small ; : e2310238, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38267815

ABSTRACT

Cesium lead halide (CsPbX3 , X = Br, Cl, and I) nanocrystals (NCs) are widely concerned and applied in many fields due to the excellent photoelectric performance. However, the toxicity of Pb and the loss of luminescence in water limit its application in vivo. A stable perovskite nanomaterial with good bioimaging properties is developed by incorporating europium (Eu) in CsPbX3 NCs followed with the surface coating of silica (SiO2 ) shell (CsPbX3 :Eu@SiO2 ). Through the surface coating of SiO2 , the luminescence stability of CsPbBr3 in water is improved and the leakage of Pb2+ is significantly reduced. In particular, Eu doping inhibits the photoluminescence quantum yield reduction of CsPbBr3 caused by SiO2 coating, and further reduces the release of Pb2+ . CsPbBr3 :Eu@SiO2 nanoparticles (NPs) show efficient luminescence in water and good biocompatibility to achieve cell imaging. More importantly, CsPb(ClBr)3 :Eu@SiO2 NPs are obtained by adjusting the halogen components, and green light and blue light are realized in zebrafish imaging, showing good imaging effect and biosafety. The work provides a strategy for advanced perovskite nanomaterials toward biological practical application.

5.
Chem Soc Rev ; 53(4): 2211-2247, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38240305

ABSTRACT

Recently, high-entropy (HE) materials have attracted increasing interest in various fields due to their unique characteristics. Rare earth (RE) elements have a similar atomic radius and gradually occupied 4f orbitals, endowing them with abundant optical, electric, and magnetic properties. Furthermore, HE-RE materials exhibit good structural and thermal stability and various functional properties, emerging as an important class of HE materials, which are on the verge of rapid development. However, a comprehensive review focusing on the introduction and in-depth understanding of HE-RE materials has not been reported to date. Thus, this review endeavors to provide a comprehensive summary of the development and research status of HE-RE materials, including alloys and ceramics, ranging from their structure, synthesis, and properties to applications. In addition, some distinctive issues of HR-RE materials related to the special electronic structure of RE are also discussed. Finally, we put forward the current challenges and future development directions of HE-RE materials. We hope that this review will provide inspiration for new design ideas and valuable references in this emerging field in the future.

6.
Small ; 20(12): e2307052, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37946708

ABSTRACT

Design of highly efficient electrocatalysts for alkaline hydrogen evolution reaction (HER) is of paramount importance for water electrolysis, but still a considerable challenge because of the slow HER kinetics in alkaline environments. Alloying is recognized as an effective strategy to enhance the catalytic properties. Lanthanides (Ln) are recognized as an electronic and structural regulator, attributed to their unique 4f electron behavior and the phenomenon known as lanthanide contraction. Here, a new class of Rh3Ln intermetallics (IMs) are synthesized using the sodium vapor reduction method. The alloying process induced an upshift of the d-band center and electron transfer from Ln to Rh, resulting in optimized adsorption and dissociation energies for H2O molecules. Consequently, Rh3Tb IMs exhibited outstanding HER activity in both alkaline environments and seawater, displaying an overpotential of only 19 mV at 10 mA cm-2 and a Tafel slope of 22.2 mV dec-1. Remarkably, the current density of Rh3Tb IMs at 100 mV overpotential is 8.6 and 5.7 times higher than that of Rh/C and commercial Pt/C, respectively. This work introduces a novel approach to the rational design of HER electrocatalysis and sheds light on the role of lanthanides in electrocatalyst systems.

7.
Chem Soc Rev ; 53(2): 714-763, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38105711

ABSTRACT

As an important strategic resource, rare earths (REs) constitute 17 elements in the periodic table, namely 15 lanthanides (Ln) (La-Lu, atomic numbers from 57 to 71), scandium (Sc, atomic number 21) and yttrium (Y, atomic number 39). In the field of catalysis, the localization and incomplete filling of 4f electrons endow REs with unique physical and chemical properties, including rich electronic energy level structures, variable coordination numbers, etc., making them have great potential in electrocatalysis. Among various RE catalytic materials, rare earth oxide (REO)-based electrocatalysts exhibit excellent performances in electrocatalytic reactions due to their simple preparation process and strong structural variability. At the same time, the electronic orbital structure of REs exhibits excellent electron transfer ability, which can reduce the band gap and energy barrier values of rate-determining steps, further accelerating the electron transfer in the electrocatalytic reaction process; however, there is a lack of systematic review of recent advances in REO-based electrocatalysis. This review systematically summarizes the synthesis, properties and applications of REO-based nanocatalysts and discusses their applications in electrocatalysis in detail. It includes the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR), carbon dioxide reduction reaction (CO2RR), methanol oxidation reaction (MOR), nitrogen reduction reaction (NRR) and other electrocatalytic reactions and further discusses the catalytic mechanism of REs in the above reactions. This review provides a timely and comprehensive summary of the current progress in the application of RE-based nanomaterials in electrocatalytic reactions and provides reasonable prospects for future electrocatalytic applications of REO-based materials.

8.
ACS Nano ; 17(22): 23103-23114, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-37930125

ABSTRACT

Rare earth (RE) elements possess electronic configurations that can provide additional pathways for tailoring the electronic structures of active elements through alloying, making it an important area of exploration in electrocatalysis. However, the large negative redox potential between RE and Pt has hindered the development of RE nanoalloys. In this study, a solid-phase synthesis strategy was employed to synthesize ternary Pt3-xIrxSc nanoparticles (NPs). By leveraging the electronegativity difference between Pt (2.28), Ir (2.20), and Sc (1.36), a charge-balance strategy was implemented to stabilize and enhance the catalytic performance of the alloy. The electron transfer from Sc to Pt/Ir results in the latter being negatively charged, and the Ir modifies the electron density of Pt, enabling favorable adsorption of active H species during the hydrogen evolution reaction (HER). Pt2IrSc exhibits enhanced HER activity at all pH values, achieving low overpotentials at 10 mA cm-2 of only 13, 18, and 25 mV in 0.5 M H2SO4, 1 M PBS, and 1 M KOH, respectively. This electrocatalyst also exhibits robust electrocatalytic stability even after 20,000 cycles. This work represents an application of the charge balance strategy to RE nanoalloys, and it is expected to inspire the design and synthesis of highly reactive RE nanoalloys.

9.
Front Plant Sci ; 14: 1263981, 2023.
Article in English | MEDLINE | ID: mdl-37810396

ABSTRACT

Introduction: Ligusticum chuanxiong Hort. is a widely used medicinal plant, but its growth and quality can be negatively affected by contamination with the heavy metal cadmium (Cd). Despite the importance of understanding how L. chuanxiong responds to Cd stress, but little is currently known about the underlying mechanisms. Methods: To address this gap, we conducted physiological and transcriptomic analyses on L. chuanxiong plants treated with different concentrations of Cd2+ (0 mg·L-1, 5 mg·L-1, 10 mg·L-1, 20 mg·L-1, and 40 mg·L-1). Results: Our findings revealed that Cd stress inhibited biomass accumulation and root development while activating the antioxidant system in L. chuanxiong. Root tissues were the primary accumulation site for Cd in this plant species, with Cd being predominantly distributed in the soluble fraction and cell wall. Transcriptomic analysis demonstrated the downregulation of differential genes involved in photosynthetic pathways under Cd stress. Conversely, the plant hormone signaling pathway and the antioxidant system exhibited positive responses to Cd regulation. Additionally, the expression of differential genes related to cell wall modification was upregulated, indicating potential enhancements in the root cell wall's ability to sequester Cd. Several differential genes associated with metal transport proteins were also affected by Cd stress, with ATPases, MSR2, and HAM3 playing significant roles in Cd passage from the apoplast to the cell membrane. Furthermore, ABC transport proteins were found to be key players in the intravesicular compartmentalization and efflux of Cd. Discussion: In conclusion, our study provides preliminary insights into the mechanisms underlying Cd accumulation and tolerance in L. chuanxiong, leveraging both physiological and transcriptomic approaches. The decrease in photosynthetic capacity and the regulation of plant hormone levels appear to be major factors contributing to growth inhibition in response to Cd stress. Moreover, the upregulation of differential genes involved in cell wall modification suggests a potential mechanism for enhancing root cell wall capabilities in isolating and sequestering Cd. The involvement of specific metal transport proteins further highlights their importance in Cd movement within the plant.

10.
Chem Sci ; 14(22): 5887-5893, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37293647

ABSTRACT

Rare earth (RE) intermetallic nanoparticles (NPs) are significant for fundamental explorations and promising for practical applications in electrocatalysis. However, they are difficult to synthesize because of the unusually low reduction potential and extremely high oxygen affinity of RE metal-oxygen bonds. Herein, intermetallic Ir2Sm NPs were firstly synthesized on graphene as a superior acidic oxygen evolution reaction (OER) catalyst. It was verified that intermetallic Ir2Sm is a new phase belonging to the C15 cubic MgCu2 type in the Laves phase family. Meanwhile, intermetallic Ir2Sm NPs achieved a mass activity of 1.24 A mgIr-1 at 1.53 V and stability of 120 h at 10 mA cm-2 in 0.5 M H2SO4 electrolyte, which corresponds to a 5.6-fold and 12-fold enhancement relative to Ir NPs. Experimental results together with density functional theory (DFT) calculations show that in the structurally ordered intermetallic Ir2Sm NPs, the alloying of Sm with Ir atoms modulates the electronic nature of Ir, thereby reducing the binding energy of the oxygen-based intermediate, resulting in faster kinetics and enhanced OER activity. This study provides a new perspective for the rational design and practical application of high-performance RE alloy catalysts.

11.
Small Methods ; 7(9): e2300177, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37287373

ABSTRACT

Owing to rapid property degradation after ambient exposure and incompatibility with conventional device fabrication process, electrical transport measurements on air-sensitive 2D materials have always been a big issue. Here, for the first time, a facile one-step polymer-encapsulated electrode transfer (PEET) method applicable for fragile 2D materials is developed, which showed great advantages of damage-free electrodes patterning and in situ polymer encapsulation preventing from H2 O/O2 exposure during the whole electrical measurements process. The ultrathin SmTe2 metals grown by chemical vapor deposition (CVD) are chosen as the prototypical air-sensitive 2D crystals for their poor air-stability, which will become highly insulating when fabricated by conventional lithographic techniques. Nevertheless, the intrinsic electrical properties of CVD-grown SmTe2 nanosheets can be readily investigated by the PEET method instead, showing ultralow contact resistance and high signal/noise ratio. The PEET method can be applicable to other fragile ultrathin magnetic materials, such as (Mn,Cr)Te, to investigate their intrinsic electrical/magnetic properties.

12.
Adv Healthc Mater ; 12(25): e2300748, 2023 10.
Article in English | MEDLINE | ID: mdl-37314429

ABSTRACT

Disease or organ damage due to unhealthy living habits, or accidents, is inevitable. Discovering an efficient strategy to address these problems is urgently needed in the clinic. In recent years, the biological applications of nanotechnology have received extensive attention. Among them, as a widely used rare earth oxide, cerium oxide (CeO2 ) has shown good application prospects in biomedical fields due to its attractive physical and chemical properties. Here, the enzyme-like mechanism of CeO2 is elucidated, and the latest research progress in the biomedical field is reviewed. At the nanoscale, Ce ions in CeO2 can be reversibly converted between +3 and +4. The conversion process is accompanied by the generation and elimination of oxygen vacancies, which give CeO2 the performance of dual redox properties. This property facilitates nano-CeO2 to catalyze the scavenging of excess free radicals in organisms, hence providing a possibility for the treatment of oxidative stress diseases such as diabetic foot, arthritis, degenerative neurological diseases, and cancer. In addition, relying on its excellent catalytic properties, customizable life-signaling factor detectors based on electrochemical techniques are developed. At the end of this review, an outlook on the opportunities and challenges of CeO2 in various fields is provided.


Subject(s)
Cerium , Nanoparticles , Precision Medicine , Oxidative Stress , Cerium/chemistry , Antioxidants , Nanoparticles/chemistry
13.
Adv Mater ; 35(28): e2302485, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37015027

ABSTRACT

For current single-atom catalysts (SACs), modulating the coordination environments of rare-earth (RE) single atoms with complex electronic orbital and flexible chemical states is still limited. Herein, cerium (Ce) SAs supported on a P, S, and N co-doped hollow carbon substrate (Ce SAs/PSNC) for the oxygen reduction reaction (ORR) are reported. The as-prepared Ce SAs/PSNC possesses a half-wave potential of 0.90 V, a turnover frequency value of 52.2 s-1 at 0.85 V, and excellent stability for the ORR, which exceeds the commercial Pt/C and most recent SACs. Ce SAs/PSNC-based liquid zinc-air batteries (ZABs) exhibit a high and stable open-circuit voltage of 1.49 V and a maximum power density of 212 mW cm-2 . As the catalyst of the air cathode, it also displays remarkable performance in flexible electronic devices. Theoretical calculations reveal that the introduction of S and P sites induces significant electronic modulations to the Ce SA active sites. The P and S dopings promote the electroactivity of Ce SAs and improve the overall site-to-site electron transfer within the Ce SAs/PSNC. This work offers a unique perspective for modulating RE-based SACs in a complex coordination environment toward superior electrocatalysis and broad applications in energy conversion and storage devices.


Subject(s)
Cerium , Humans , Carbon , Electric Power Supplies , Electrodes , Hypoxia , Oxygen
14.
Small ; 19(33): e2301392, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37086136

ABSTRACT

As an important lanthanide (Ln)-based functional materials, the Ln chalcogenides possess unique properties and various applications. However, the controllable synthesis of Ln chalcogenide nanocrystals still faces great challenges because of the rather poor affinity between Ln and chalcogenide ions (S, Se, Te) as well as strong preference of combination with existed oxygen. Herein, a facile but general heterogeneous nucleation synthetic strategy is established toward a series of colloidal ternary Cu Ln sulfides nanocrystals using the Ln dithiocarbamates and CuI as precursors. To extend this synthetic protocol, similar strategy is used to prepare six kinds of high quality CuLnS2 nanocrystals, while the bulk ones are only obtained by the traditional solid-state reaction at rigorous condition. Importantly, high-entropy nanocrystals CuLnS2 and CuEux Ln2-x S3 which contain six Ln elements (Nd, Sm, Gd, Tb, Dy) are readily obtained by the co-decomposed process attributed to their similar diffusion speed. As a proof-of-concept application, CuEu2 S3 nanocrystals showed efficient photocatalytic hydrogen production properties.

15.
Adv Mater ; 35(25): e2300313, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36939167

ABSTRACT

Osteosarcoma occurs in children and adolescents frequently and leads to a high fatality rate. Although surgical resection is the most common methods in clinic, patients always suffer from tumor metastasis and recurrence and it is difficult for them to self-repair large bone defects. Furthermore, the postoperative infection from bacteria triggers an inflammatory response and hinders the bone-repair process. This work demonstrates a gadolinium (Gd)-complex and molybdenum sulfide (MoS2 ) co-doped N-acryloyl glycinamide (NAGA)/gelatin methacrylate (Gel-MA) multifunctional hydrogel (GMNG). The combination between NAGA and Gel-MA endows the GMNG with attractive mechanical properties and controllable degradation ability. The MoS2 improves the hydrogel system, which has excellent photothermal ability to kill tumor cells and inhibit bacterial infection both in vitro and in vivo. Based on the Gd-complex, the magnetic resonance imaging (MRI) effect can be used to monitor the position and degradation situation of the hydrogel. Notably, accompanied by the degradation of GMNG hydrogel, the gradually released Gd3+ from the hydrogel exhibits osteogenic property and could promote new bone formation efficiently in vivo. Therefore, this strategy supplies a method to prepare multifunctional bone-defect-repair materials and is expected to represent a significant guidance and reference to the development of biomaterials for bone tissue engineering.


Subject(s)
Bone Neoplasms , Tissue Engineering , Child , Humans , Adolescent , Molybdenum , Neoplasm Recurrence, Local , Bone Regeneration , Tissue Scaffolds , Osteogenesis , Bone Remodeling , Hydrogels , Bone Neoplasms/therapy
16.
ACS Nano ; 17(5): 4433-4444, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36802532

ABSTRACT

Rational design of multifunctional biomaterials with customized architecture and on demand bioactivity is of great significance for bone tissue engineering (BTE) in modern society. Herein, a versatile therapeutic platform has been established by integrating cerium oxide nanoparticles (CeO2 NPs) into bioactive glass (BG) to fabricate three-dimensional (3D)-printed scaffolds, achieving a sequential therapeutic effect against inflammation and promoting osteogenesis toward bone defect. The antioxidative activity of CeO2 NPs plays a crucial role in alleviating the oxidative stress upon formation of bone defects. Subsequently, CeO2 NPs exert a promotion effect on the proliferation and osteogenic differentiation of rat osteoblasts through enhancing mineral deposition and alkaline phosphatase and osteogenic gene expression. Strikingly, the incorporation of CeO2 NPs bestows on the BG scaffolds greatly reinforced mechanical properties, improved biocompatibility, adequate cell adhesion, elevated osteogenic capability, and multifunctional performance in a single platform. In vivo studies on the treatment of rat tibial defect confirmed the better osteogenic properties of CeO2-BG scaffolds compared with pure BG scaffolds. Additionally, the employment of the 3D printing technique creates a proper porous microenvironment around the bone defect, which further facilitates the cell in-growth and new bone formation. This report provides a systematic study on CeO2-BG 3D-printed scaffolds prepared by simple ball milling method, achieving sequential and integral treatment in BTE based on a single platform.


Subject(s)
Osteogenesis , Tissue Scaffolds , Rats , Animals , Bone Regeneration , Tissue Engineering/methods , Glass , Printing, Three-Dimensional
17.
JACS Au ; 3(1): 216-226, 2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36711089

ABSTRACT

Cesium lead halide (CsPbX3, X = Br, Cl, I) perovskite nanocrystals (NCs) possess tunable band gaps across the entire visible spectral range and are promising for various optoelectronic device applications. However, poor performance in adverse conditions limits their further development in practical optoelectronics. Herein, highly stable perovskite NCs are developed by doping europium(II) (Eu2+) into the B-site of CsPbBr3 with negligible lattice distortion/strain. Eu2+-doped CsPbBr3 NCs exhibit tunable green-to-cyan emissions, high photoluminescence quantum yield, and good resistance to harsh conditions, including ultraviolet irradiation, erosion of moisture, and corrosion of polar solvent molecules. In particular, the thermal stability of CsPbBr3 NCs after Eu2+ doping is greatly enhanced under continuous heating in air, while exhibiting the emissions of Eu2+. Furthermore, a Eu2+-doped CsPbBr3 NC-based cyan light-emitting diode is fabricated, which exhibits narrow exciton emission driven under different current densities. This work would open the avenue to develop the rational lanthanide ion doping strategy for further advancing perovskite nanomaterials toward practical applications.

18.
Chem Sci ; 13(42): 12367-12373, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36382279

ABSTRACT

CoF2, with a relatively high theoretical capacity (553 mA h g-1), has been attracting increasing attention in the energy storage field. However, a facile and controllable synthesis of monodispersed CoF2 and CoF2-based nano-heterostructures have been rarely reported. In this direction, an eco-friendly and precisely controlled colloidal synthesis strategy to grow uniformly sized CoF2 nanorods and LiF-tipped CoF2-nanorod heterostructures based on a seeded-growth method is established. The unveiled selective growth of LiF nanoparticles onto the two end tips of the CoF2 nanorods is associated with the higher energy of tips, which favors the nucleation of LiF nanocrystals. Notably, it was found that LiF could protect CoF2 from corrosion even after 9 months of aging. In addition, the as-obtained heterostructures were employed in supercapacitors and lithium sulfur batteries as cathode materials. The heterostructures consistently exhibited higher specific capacities than the corresponding two single components in both types of energy storage devices, making it a potential electrode material for energy storage applications.

19.
Angew Chem Int Ed Engl ; 61(45): e202212251, 2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36109346

ABSTRACT

Ultrathin nanowires (NWs) have always attracted the attention of researchers due to their unique properties, but their facile synthesis is still a great challenge. Herein we developed a general method for the synthesis of rare earth (RE) oxide ultrathin NWs at atmospheric pressure and low temperature (50 °C). The formation mechanism of ultrathin NWs lies in two aspects: thermodynamic advantage of one dimensional (1D) growth at low temperature, and supplement of effective monomers. As an extension, fifteen kinds of RE oxide ultrathin NWs were synthesized through this strategy, and they all exhibited polymer-like behaviors. Meanwhile, the high viscosity, organic gel, wet- and electro-spinning of Ce-Mo-O NWs were studied in detail, demonstrating the similarity of ultrathin inorganic NWs to polymers. In addition, the Ce-Mo-O ultrathin NWs were used as photocatalysts for toluene oxidation and showed excellent performance with toluene conversion ratio of 83.8 %, suggesting their potential application in organic photocatalysis.

20.
Skin Res Technol ; 28(5): 719-728, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35785442

ABSTRACT

BACKGROUND: Facial skin characteristics and appearance vary according to ethnicity. While much of this knowledge is derived from the Caucasian population, lately there have been efforts to gain such understanding in various regions in Asia.  In this paper, we have built an understanding of such features in Indonesia. In Indonesia, a section of females wears a traditional veil (hijab) to cover the scalp and part of face. The influence of the hijab on facial skin attributes was also investigated. METHODS: In a cross-sectional observational study design involving 419 female volunteers in Jakarta, Indonesia, facial skin attributes (colour, radiance, hydration, trans-epidermal water loss [TEWL], wrinkles, fine lines, pores, and sebum levels) and conditions (melasma, post-inflammatory hyperpigmentation (PIH), solar lentigines/ senile lentigines, seborrheic keratoses and acne) were assessed by trained operators and dermatologists using standard validated instruments and scales. RESULTS: With age, facial skin colour showed darkening in cheek; forehead on the other hand showed slight lightening. The skin evenness and radiance decreased, substantially. Aging attributes measured in terms of lines, wrinkles, and under-eye dark circles showed deterioration with age; the decline was progressively faster than colour change. Facial image data analysis corroborated these findings. Skin hydration remained similar across the age groups even though the skin barrier function measured in terms of TEWL improved with age. Sebum levels in the skin were similar up to the age of 50 but declined in the next group of 50-60 year. Pore severity increased with age. Melasma, seborrheic keratosis and PIH showed a high prevalence (>∼50%) at the young age group (20-30 years), itself. Melasma prevalence attained 100% in the age group of 41-50 year and onwards, and its severity similarly showed a steady rise with age. PIH on the other hand showed a steady decline with age. Solar lentigines prevalence (∼30%) did not change much across age groups, and the severity scores were similar in age groups up to 50 year but increased substantially in 51-60-year age groups. Seborrheic keratosis was similar (∼47%) in age groups up 20-40 year but steadily increased in upper age groups. Its severity was similar in the age groups of 20-30 year and 31-40 year but showed a two-fold increase in subsequent age groups. Acne was 10% in the age group of 20-30 year and declined gradually to 0.7% in the 51-60-year age group. Hijab wearers showed slight protection in skin colour darkening and improvement of evenness and radiance but were similar on aging (fine lines and wrinkles on crow's feet, under eye and peri-oral areas) markers to non-wearers. In general, in majority of age-groups, hijab wearers showed a higher prevalence of melasma, solar/senile lentigines, seborrheic keratosis and PIH.


Subject(s)
Acne Vulgaris , Hyperpigmentation , Keratosis, Seborrheic , Lentigo , Melanosis , Skin Aging , Adult , Cross-Sectional Studies , Female , Humans , Hyperpigmentation/epidemiology , Indonesia/epidemiology , Middle Aged , Water , Young Adult
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