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1.
Environ Int ; 185: 108516, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38447452

ABSTRACT

Climate change is endangering the soil carbon stock of alpine grasslands on the Qinghai-Tibetan Plateau (QTP), but the limited comprehension regarding the mechanisms that sustain carbon storage under hydrothermal changes increases the uncertainty associated with this finding. Here, we examined the relative abundance of soil microbial keystone taxa and their functional potentials, as well as their influence on soil carbon storage with increased precipitation across alpine grasslands on the QTP, China. The findings indicate that alterations in precipitation significantly decreased the relative abundance of the carbon degradation potentials of keystone taxa, such as chemoheterotrophs. The inclusion of keystone taxa and their internal functional potentials in the two best alternative models explained 70% and 63% of the variance in soil organic carbon (SOC) density, respectively. Moreover, we found that changes in chemoheterotrophs had negative effects on SOC density as indicated by a structural equation model, suggesting that some specialized functional potentials of keystone taxa are not conducive to the accumulation of carbon sink. Our study offers valuable insights into the intricate correlation between precipitation-induced alterations in soil microbial keystone taxa and SOC storage, highlighting a rough categorization is difficult to distinguish the hidden threats and the importance of incorporating functional potentials in SOC storage prediction models in response to changing climate.


Subject(s)
Carbon , Soil , Soil/chemistry , Carbon/analysis , Grassland , Climate Change , China
2.
RSC Adv ; 14(3): 1962-1969, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38196903

ABSTRACT

Zero-dimensional (0D)-two-dimensional (2D) hybrid photodetectors have received widespread attention due to their outstanding photoelectric performances. However, these devices with high performances mainly employ quantum dots that contain toxic elements as sensitizing layers, which restricts their practical applications. In this work, we used eco-friendly AgInGaS quantum dots (AIGS-QDs) as a highly light-absorbing layer and molybdenum diselenide (MoSe2) as a charge transfer layer to construct a 0D-2D hybrid photodetector. Notably, we observed that MoSe2 strongly quenches the photoluminescence (PL) of AIGS-QDs and decreases the decay time of PL in the MoSe2/AIGS-QDs heterojunction. The MoSe2/AIGS-QDs hybrid photodetector demonstrates a responsivity of 14.3 A W-1 and a high detectivity of 6.4 × 1011 Jones. Moreover, the detectivity of the hybrid phototransistor is significantly enhanced by more than three times compared with that of the MoSe2 photodetector. Our work suggests that 0D-2D hybrid photodetectors with multiplex I-III-VI QDs provide promising potential for future high-sensitivity photodetectors.

3.
Dalton Trans ; 52(23): 8135-8141, 2023 Jun 13.
Article in English | MEDLINE | ID: mdl-37248846

ABSTRACT

Brønsted-base active sites on a Pd4L2 cage facilitates enhanced catalytic efficiency, wide substrate scope and high turnover number (TON) for the one-pot photooxidation/Knoevenagel condensation reaction under mild conditions.

4.
Chem Commun (Camb) ; 59(36): 5365-5374, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37070699

ABSTRACT

Metal halide perovskite nanocrystals (NCs) have been widely studied for application in photonics and optoelectronics due to their excellent photoelectric properties. Perovskite NCs with narrow luminescence linewidth and high photoluminescence quantum yield are excellent assembly modules for building large-scale NC superlattices. The coupling of optics and electricity in such excellent aggregates gives them exceptional collective photoelectric performance, such as superfluorescence, red-shifted emission, coupling-enhanced electron transport, etc. Perovskite NC superlattices are expected to become another hot research topic in optoelectronics. Here, we focus on the collective behavior of superlattices and review the recent progress of the self-assembly, collective photoelectric properties, and applications of perovskite NC superlattices. Finally, a few challenges and prospects are indicated.

5.
Saudi Pharm J ; 31(4): 554-568, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37063438

ABSTRACT

Ferroptosis is a new type of cell death discovered in recent years that distinguishes from apoptosis and necrosis, mainly caused by the imbalance between the production and degradation of lipid reactive oxygen species in cells. Although the mechanism of ferroptosis is not yet clear, the phenomenon of ferroptosis has attracted widespread attention from researchers and has become a new hotspot in anti-tumor research. Studies have shown that ferroptosis is involved in the occurrence and development of a variety of diseases such as nervous system diseases, cardiovascular diseases and cancer. And inhibiting or inducing the occurrence of ferroptosis can effectively intervene in related diseases. At the same time, nanotechnology, by virtue of its distinct advantages, has been widely used in the development of nanodrug delivery systems. This review outlines current the advance on the intersection of ferroptosis and biomedical nanotechnology. In this review, the discovery and characteristics of ferroptosis, the mechanism of occurrence and the relationship with disease are summarized. More importantly, we summarized the strategies for inducing ferroptosis based on nanoparticulate drug delivery systems for cancer treatment.

6.
Front Psychiatry ; 14: 1138205, 2023.
Article in English | MEDLINE | ID: mdl-37032928

ABSTRACT

Objective: Major depressive disorder (MDD) has a relapse rate that cannot be ignored and places a tremendous burden on the patient in the prevention and treatment process. Yoga, a combination of physical and mental exercises, is effective and acceptable for the adjunctive treatment of MDD. This study aimed to explore further the evidence of yoga's efficacy for patients with MDD. Methods: PubMed, Embase, Cochrane library, PsycINFO, SinoMed, CNKI, Wanfang, and VIP databases from their inception to 13 October 2022 were searched by a pre-defined search strategy. RCTs of patients with MDD who met diagnostic criteria for yoga treatment were included. RoB2.0 was used to evaluate the quality of the literature. Improvement in depressive symptoms was assessed by the Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HAMD), or other scales were used as primary outcome indicators, and improvement in anxiety was assessed by the Hamilton Anxiety Scale (HAMA) and State-Trait Anxiety Inventory (STAI) scale as secondary outcome indicators. RR and Cohen's d at 95% CI were used as effect size estimates, and Q and I2 were used to evaluate the size of heterogeneity, with a p-value less than 0.05 indicating statistical significance. Results: Thirty-four RCT studies, including 1,269 patients in the treatment group and 1,072 patients in the control group, 48.4% of whom were women, were included in the study. Compared to the control group, the BDI-II results yielded a moderate effect of yoga on the improvement of depressive symptoms (Cohen's d = -0.60; 95% CI: -1.00 to -0.21; p < 0.01), the HAMD results yielded a moderate improvement of yoga on the severity of depressive symptoms (Cohen's d = -0.64; 95% CI: -0.98 to -0.30; p < 0.01), and the STAI results can be concluded that yoga had a negligible effect on the improvement of the level of anxiety (Cohen's d = -0.26; 95% CI: -0.48 to -0.04; p = 0.02). No adverse events occurred in the yoga group during the treatment. Conclusion: Yoga can improve depressive symptoms and anxiety in patients with MDD and has a safe and wide patient acceptance. Systematic review registration: [https://www.crd.york.ac.uk/prospero/], identifier [PROSPERO, CRD42022373282].

7.
Angew Chem Int Ed Engl ; 61(42): e202209879, 2022 Oct 17.
Article in English | MEDLINE | ID: mdl-36036434

ABSTRACT

Artificial hosts with rich conformational dynamics are attractive to supramolecular chemists due to their adaptive guest-binding properties and enzyme-like catalytic functions. We report here the adaptive self-assembly and host-guest catalysis of a new water-soluble organo-palladium host (Pd2 L2 ) built from a pyridinium-bonded macrocyclic ligand (L) and cis-blocked palladium corners (Pd). While the direct self-assembly of L with Pd gives rise to a dynamic mixture of products, both neutral polyaromatic hydrocarbons and an anionic polyoxometalate cluster (W10 O32 4- ) can template the dominant formation of the Pd2 L2 host. Guest-adaptive conformational changes and induced-fit cavity deformation of the Pd2 L2 host have been clearly observed in the crystal structures. Moreover, the installation of the electron-rich W10 O32 4- cluster within the cationic redox-active host (W10 O32 ⊂Pd2 L2 ) facilitates the efficient and selective C-H photooxidation of toluene derivatives to aldehyde products under mild conditions, thus representing an ideal platform for green supramolecular catalysis.

8.
Inorg Chem ; 61(23): 8854-8860, 2022 Jun 13.
Article in English | MEDLINE | ID: mdl-35642338

ABSTRACT

We present here the coordination self-assembly of a new heteroleptic (bpyPd)4L1L22 coordination complex (1) from one novel pyridinium-functionalized bis-2,4,6-tris(pyridin-3-yl)-1,3,5-triazine (bis-3-TPT, L1) macrocyclic ligand, two separate 3-TPT (L2) ligands, and four cis-blocking bpyPd(NO3)2 (bpy = 2,2'-bipyridine). While homoleptic self-assemblies with either L1 or L2 gave dynamic mixtures of products, a single thermodynamic heteroleptic complex was obtained driven by the shape complementarity of building blocks. Moreover, the redox-active nature of the heteroleptic assembly facilitates the highly efficient catalytic aerobic photo-oxidation of aromatic secondary alcohols under mild conditions.

9.
J Am Chem Soc ; 144(9): 4244-4253, 2022 03 09.
Article in English | MEDLINE | ID: mdl-35195993

ABSTRACT

Chiral luminescent lanthanide-organic cages have many potential applications in enantioselective recognition, sensing, and asymmetric catalysis. However, due to the paucity of structures and their limited cavities, host-guest chemistry with lanthanide-organic cages has remained elusive so far. Herein, we report a guest-driven self-assembly and chiral induction approach for the construction of otherwise inaccessible Ln4L4-type (Ln = lanthanide ions, i.e., EuIII, TbIII; L = ligand) tetrahedral hosts. Single crystal analyses on a series of host-guest complexes reveal remarkable guest-adaptive cavity breathing on the tetrahedral cages, reflecting the advantage of the variation tolerance on coordination geometry of the f-elements. Meanwhile, noncovalent confinement of pyrene within the lanthanide cage not only leads to diminishment of its excimer emission but also facilitates guest to host energy transfer, opening up a new sensitization window for the lanthanide luminescence on the cage. Moreover, stereoselective self-assembly of either Λ4- or Δ4- type Eu4L4 cages has been realized via chiral induction with R/S-BINOL or R/S-SPOL templates, as confirmed by NMR, circular dichroism (CD), and circularly polarized luminescence (CPL) with high dissymmetry factors (glum) up to ±0.125.


Subject(s)
Lanthanoid Series Elements , Circular Dichroism , Europium/chemistry , Lanthanoid Series Elements/chemistry , Luminescence , Stereoisomerism
10.
J Phys Condens Matter ; 34(6)2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34715688

ABSTRACT

Recently, the effect of dimensional control on the optoelectronic performance of two-dimensional (2D)/three-dimensional (3D) single perovskites has been confirmed. However, how the dimensional change affects the photoelectric properties of 2D/3D all-inorganic double perovskites remains unclear. In this study, we present a detailed theoretical research on a comparison between the optoelectronic properties of 3D all-inorganic double perovskite Cs2AgBiBr6and recently reported 2D all-inorganic double perovskite Cs4AgBiBr8with Ruddlesden-Popper (RP) structure based on density functional theory calculations. The results demonstrate the charge carrier mobility and absorption coefficients in the visible spectrum of Cs4AgBiBr8(2D) is poorer than Cs2AgBiBr6(3D). Moreover, the value of exciton-binding energy for 2D RP all-inorganic double perovskite Cs4AgBiBr8(720 meV) is 3 times larger than that of 3D all-inorganic double perovskite Cs2AgBiBr6(240 meV). Our works indicate that Cs4AgBiBr8(2D) is a promising material for luminescent device, while Cs2AgBiBr6(3D) may be suitable for photovoltaic applications. This study provides a theoretical guidance for the understanding of 2D RP all-inorganic double perovskite with potential applications in photo-luminescent devices.

11.
J Am Chem Soc ; 143(39): 16087-16094, 2021 10 06.
Article in English | MEDLINE | ID: mdl-34553600

ABSTRACT

One important feature of enzyme catalysis is the induced-fit conformational change after binding substrates. Herein, we report a biomimetic water-soluble molecular capsule featuring adaptive structural change toward substrate binding, which offers an ideal platform for efficient photocatalysis. The molecular capsule was coordination-assembled from three anthracene-bridged bis-TPT [TPT = 2,4,6-tris(4-pyridyl)-1,3,5-triazine] ligands and six (bpy)Pd(NO3)2 (bpy = 2,2'-bipyridine). Once substrates bind to its hydrophobic cavity, this capsule would undergo quantitative capsule-to-bowl transformation. Visible-light absorption brought about by both the anthracene units and the charge-transfer absorption on the late-formed quintuple π-π stacked host-guest complex efficiently facilitates aerobic photooxidation for the sulfide guests by visible-light irradiation under mild conditions. Desired turnover numbers and product selectivity (sulfoxide over sulfone) have been achieved by the transformable nature of the catalyst and the hydrophilicity of the sulfoxide product. Such a photocatalytic process enabled by an adaptive coordination capsule and substrates as the allosteric effector paves the way for constructing artificial systems to mimic enzyme catalysis.


Subject(s)
2,2'-Dipyridyl , Biomimetics , Photochemical Processes , 2,2'-Dipyridyl/chemistry , Catalysis , Light , Molecular Structure , Oxidation-Reduction
12.
Chem Asian J ; 16(11): 1392-1397, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33886167

ABSTRACT

Herein, we report a comprehensive study on the lanthanide-directed coordination self-assembly with two bis-tetradentate acylhydrazone ligands H4 L1 and H4 L2 . Multifarious outcomes, which are base- and metal-dependent, were revealed by NMR, ESI-TOF-MS and X-ray crystallography. In the absence of base, bent H4 L1 was assembled into dinuclear double-strand helicate Ln2 (H2 L1 )2 by partially-deprotonated assembly with La, Sm or Eu, while trinuclear Ln3 (H2 L1 )3 with Yb or Lu. For linear H4 L2 , infinite 1D zig-zag metal-organic polymeric chain (Ln2 H2 L2 )n was obtained. However, complete deprotonated L1 and L2 assembled into discrete trinuclear Ln3 (L1 /2 )3 and tetranuclear Ln4 (L1 /2 )4 macrocyclic structures under the basic condition. For these, there are multiple possible isomers coexisting in the solution which were enumerated and simulated with molecular mechanic modeling. Visible-light sensitized NIR emissions on the Yb complexes have been observed, endowing them potential application in photofunctional materials.

13.
J Am Chem Soc ; 143(4): 2016-2024, 2021 02 03.
Article in English | MEDLINE | ID: mdl-33471998

ABSTRACT

Stimuli-responsive structural transformations between discrete coordination supramolecular architectures not only are essential to construct smart functional materials but also provide a versatile molecular-level platform to mimic the biological transformation process. We report here the controlled self-assembly of three topologically unprecedented conjoined twin-cages, i.e., one stapled interlocked Pd12L6 cage (2) and two helically isomeric Pd6L3 cages (3 and 4) made from the same cis-blocked palladium corners and a new bis-bidentate ligand (1). While cage 2 features three mechanically coupled cavities, cages 3 and 4 are topologically isomeric helicate-based twin-cages based on the same metal/ligand stoichiometry. Sole formation of cage 2 or a dynamic mixture of cages 3 and 4 can be controlled by changing the solvents employed during the self-assembly. Structural conversions between cages 3 and 4 can be triggered by changes in both temperature/solvent and induced-fit guest encapsulations. Well-controlled interconversion between such topologically complex superstructures may lay a solid foundation for achieving a variety of functions within a switchable system.

14.
Angew Chem Int Ed Engl ; 59(52): 23569-23573, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-32902925

ABSTRACT

We report here a guest-reaction-induced mitosis-like host transformation from a known Pd4 L2 cage 1 to a conjoined Pd6 L3 twin-cage 2 featuring two separate cavities. The encapsulation of 1-hydroxymethyl-2-naphthol (G1), a known ortho-quinone methide (o-QMs) precursor, within the hydrophobic cavity of cage 1 is found crucial to realize the cage to twin-cage conversion. Confined G1 molecules within the nanocavity undergo self-coupling dimerization reaction to form 2,2'-dihydroxy-1,1'-dinaphthylmethane (G2) which then triggers the cage to twin-cage mitosis. The same conversion also proceeds, in a much faster rate, via the direct templation of G2, confirming the induced-fit transformation mechanism. The structure of the (G2)2 ⊂2 host-guest complex has been established by X-ray crystallographic study, where cis- to trans- conformational switch on one bridging ligand is revealed.

15.
J Am Chem Soc ; 140(14): 4869-4876, 2018 04 11.
Article in English | MEDLINE | ID: mdl-29534562

ABSTRACT

Transformations within container-molecules provide a good alternative between traditional homogeneous and heterogeneous catalysis, as the containers themselves can be regarded as single molecular nanomicelles. We report here the designed-synthesis of a water-soluble redox-active supramolecular Pd4L2 cage and its application in the encapsulation of aromatic molecules and polyoxometalates (POMs) catalysts. Compared to the previous known Pd6L4 cage, our results show that replacement of two cis-blocked palladium corners with p-xylene bridges through pyridinium bonds formation between the 2,4,6-tri-4-pyridyl-1,3,5-triazine (TPT) ligands not only provides reversible redox-activities for the new Pd4L2 cage, but also realizes the expansion and subdivision of its internal cavity. An increased number of guests, including polyaromatics and POMs, can be accommodated inside the Pd4L2 cage. Moreover, both conversion and product selectivity (sulfoxide over sulfone) have also been much enhanced in the desulfurization reactions catalyzed by the POMs@Pd4L2 host-guest complexes. We expect that further photochromic or photoredox functions are possible taking advantage of this new generation of organo-palladium cage.

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