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"Chen, Fu"
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شعر من الصين
يتناول كتاب (شعر من الصين) والذي قام بتأليفه (نظم ماوتسي تونغ) في حوالي (110) صفحة من القطع المتوسط موضوع (الشعر الصيني) مستعرضا أبرز القصائد وشرحها التالية : القصيدة الأولى : تشانغ تشا، القصيدة الثانية : عش الكراكي الأصفر، القصيدة الثامنة : ثلاث مقطوعات، القصيدة السابعة عشرة : الخالدان، القصيدة الثامنة عشرة : طرد إله الطاعون.
Book
Photocatalytic decarboxylative alkylations mediated by triphenylphosphine and sodium iodide
Most photoredox catalysts in current use are precious metal complexes or synthetically elaborate organic dyes, the cost of which can impede their application for large-scale industrial processes. We found that a combination of triphenylphosphine and sodium iodide under 456-nanometer irradiation by blue light–emitting diodes can catalyze the alkylation of silyl enol ethers by decarboxylative coupling with redox-active esters in the absence of transition metals. Deaminative alkylation using Katritzky’s N-alkylpyridinium salts and trifluoromethylation using Togni’s reagent are also demonstrated. Moreover, the phosphine/iodide-based photoredox system catalyzes Minisci-type alkylation of N-heterocycles and can operate in tandem with chiral phosphoric acids to achieve high enantioselectivity in this reaction.
Journal Article
Investigation of the Characteristics and Antibacterial Activity of Polymer-Modified Copper Oxide Nanoparticles
The proliferation of drug-resistant pathogens continues to increase, giving rise to serious public health concerns. Many researchers have formulated metal oxide nanoparticles for use as novel antibacterial agents. In the present study, copper oxide (CuO) was synthesized by simple hydrothermal synthesis, and doping was performed to introduce different polymers onto the NP surface for bacteriostasis optimization. The polymer-modified CuO NPs were analyzed further with XRD, FTIR, TEM, DLS and zeta potential to study their morphology, size, and the charge of the substrate. The results indicate that polymer-modified CuO NPs had a significantly higher bacteriostatic rate than unmodified CuO NPs. In particular, polydopamine (PDA)-modified CuO (CuO-PDA) NPs, which carry a weakly negative surface charge, exhibited excellent antibacterial effects, with a bacteriostatic rate of up to 85.8 ± 0.2% within 3 h. When compared to other polymer-modified CuO NPs, CuO-PDA NPs exhibited superior bacteriostatic activity due to their smaller size, surface charge, and favorable van der Waals interactions. This may be attributed to the fact that the CuO-PDA NPs had relatively lipophilic structures at pH 7.4, which increased their affinity for the lipopolysaccharide-containing outer membrane of the Gram-negative bacterium Escherichia coli.
Journal Article
Recent Advances on Natural Aryl-C-glycoside Scaffolds: Structure, Bioactivities, and Synthesis—A Comprehensive Review
Aryl-C-glycosides, of both synthetic and natural origin, are of great significance in medicinal chemistry owing to their unique structures and stability towards enzymatic and chemical hydrolysis as compared to O-glycosides. They are well-known antibiotics and potent enzyme inhibitors and possess a wide range of biological activities such as anticancer, antioxidant, antiviral, hypoglycemic effects, and so on. Currently, a number of aryl-C-glycoside drugs are on sale for the treatment of diabetes and related complications. This review summarizes the findings on aryl-C-glycoside scaffolds over the past 20 years, concerning new structures (over 200 molecules), their bioactivities—including anticancer, anti-inflammatory, antioxidant, antivirus, glycation inhibitory activities and other pharmacological effects—as well as their synthesis.
Journal Article
Hygroscopic holey graphene aerogel fibers enable highly efficient moisture capture, heat allocation and microwave absorption
Aerogel fibers have been recognized as the rising star in the fields of thermal insulation and wearable textiles. Yet, the lack of functionalization in aerogel fibers limits their applications. Herein, we report hygroscopic holey graphene aerogel fibers (LiCl@HGAFs) with integrated functionalities of highly efficient moisture capture, heat allocation, and microwave absorption. LiCl@HGAFs realize the water sorption capacity over 4.15 g g
−1
, due to the high surface area and high water uptake kinetics. Moreover, the sorbent can be regenerated through both photo-thermal and electro-thermal approaches. Along with the water sorption and desorption, LiCl@HGAFs experience an efficient heat transfer process, with a heat storage capacity of 6.93 kJ g
−1
. The coefficient of performance in the heating and cooling mode can reach 1.72 and 0.70, respectively. Notably, with the entrapped water, LiCl@HGAFs exhibit broad microwave absorption with a bandwidth of 9.69 GHz, good impedance matching, and a high attenuation constant of 585. In light of these findings, the multifunctional LiCl@HGAFs open an avenue for applications in water harvest, heat allocation, and microwave absorption. This strategy also suggests the possibility to functionalize aerogel fibers towards even broader applications.
Functionalization of aerogel fibers, characterized by high porosity and low thermal conductivity, to obtain multifunctional materials is highly desirable. Here the authors report hygroscopic holey graphene aerogel fibers hosting LiCl salt, enabling moisture capture, heat allocation, and microwave absorption performance.
Journal Article
Carbon-doped SnS2 nanostructure as a high-efficiency solar fuel catalyst under visible light
Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an
l
-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS
2
(SnS
2
-C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO
2
to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS
2
lattice, resulting in different photophysical properties as compared with undoped SnS
2
. This SnS
2
-C photocatalyst significantly enhances the CO
2
reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS
2
-C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO
2
reduction under visible light, where the in situ carbon-doped SnS
2
nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.
Photocatalytic reduction of CO
2
to hydrocarbons is a promising route to both CO
2
utilization and renewable fuel production. Here the authors identify that carbon-doped SnS
2
possesses a high catalytic efficiency towards CO
2
reduction owing to low photogenerated charge recombination rates.
Journal Article
The future of pharmaceuticals: Artificial intelligence in drug discovery and development
Artificial intelligence (AI) is revolutionizing traditional drug discovery and development models by seamlessly integrating data, computational power, and algorithms. This synergy enhances the efficiency, accuracy, and success rates of drug research, shortens development timelines, and reduces costs. Coupled with machine learning (ML) and deep learning (DL), AI has demonstrated significant advancements across various domains, including drug characterization, target discovery and validation, small molecule drug design, and the acceleration of clinical trials. Through molecular generation techniques, AI facilitates the creation of novel drug molecules, predicting their properties and activities, while virtual screening (VS) optimizes drug candidates. Additionally, AI enhances clinical trial efficiency by predicting outcomes, designing trials, and enabling drug repositioning. However, AI's application in drug development faces challenges, including the need for robust data-sharing mechanisms and the establishment of more comprehensive intellectual property protections for algorithms. AI-driven pharmaceutical companies must also integrate biological sciences and algorithms effectively, ensuring the successful fusion of wet and dry laboratory experiments. Despite these challenges, the potential of AI in drug development remains undeniable. As AI technology evolves and these barriers are addressed, AI-driven therapeutics are poised for a broader and more impactful future in the pharmaceutical industry.
[Display omitted]
•AI has three fundamental elements in drug R&D.•The applications of AI have been summarized in drug discovery.•The various applications of AI have been outlined within the pharmaceutical industry.•The existing challenges in AI for drug R&D and potential solutions are identified.
Journal Article
ARF-Crack: rotation invariant deep fully convolutional network for pixel-level crack detection
Autonomous detection of structural defect from images is a promising, but also challenging task to replace manual inspection. With the development of deep learning algorithms, several studies have adopted deep convolutional neural networks (CNN) or fully convolutional networks (FCN) to detect cracks in pixel-level. However, a fundamental property of cracks, that they are rotation invariant, has never been exploited. Although the rotation-invariant property can be implicitly learned by data augmentation, the network needs more parameters to learn features of different orientations and thus tend to overfit the training data. In this study, a rotation-invariant FCN called ARF-Crack is proposed that utilizes the rotation-invariant property of cracks explicitly. The architecture of a state-of-the-art FCN called DeepCrack for pixel-level crack detection is adopted and revised where active rotating filters (ARFs) are used to encode the rotation-invariant property into the network. The proposed ARF-Crack is evaluated on several benchmark datasets including concrete cracks, pavement cracks and corrosion images. The experimental results show that the proposed ARF-Crack requires less number of network parameters and achieves the highest average precision values for all the benchmark datasets compared to other approaches. The proposed ARF-Crack has the potential of detecting other rotation-invariant defects.
Journal Article
Self-hydrogenated shell promoting photocatalytic H2 evolution on anatase TiO2
As one of the most important photocatalysts, TiO
2
has triggered broad interest and intensive studies for decades. Observation of the interfacial reactions between water and TiO
2
at microscopic scale can provide key insight into the mechanisms of photocatalytic processes. Currently, experimental methodologies for characterizing photocatalytic reactions of anatase TiO
2
are mostly confined to water vapor or single molecule chemistry. Here, we investigate the photocatalytic reaction of anatase TiO
2
nanoparticles in water using liquid environmental transmission electron microscopy. A self-hydrogenated shell is observed on the TiO
2
surface before the generation of hydrogen bubbles. First-principles calculations suggest that this shell is formed through subsurface diffusion of photo-reduced water protons generated at the aqueous TiO
2
interface, which promotes photocatalytic hydrogen evolution by reducing the activation barrier for H
2
(H–H bond) formation. Experiments confirm that the self-hydrogenated shell contains reduced titanium ions, and its thickness can increase to several nanometers with increasing UV illuminance.
Photocatalytic water splitting on TiO
2
is a promising route to H
2
fuel production, but the mechanistic pathway at the water–TiO
2
interface remains poorly understood. Here, using liquid environmental TEM and first-principles calculations, the authors unveil the formation of a self-hydrogenated shell on the TiO
2
surface that further promotes H
2
production.
Journal Article
Integration of a (–Cu–S–)n plane in a metal–organic framework affords high electrical conductivity
Designing highly conducting metal–organic frameworks (MOFs) is currently a subject of great interest for their potential applications in diverse areas encompassing energy storage and generation. Herein, a strategic design in which a metal–sulfur plane is integrated within a MOF to achieve high electrical conductivity, is successfully demonstrated. The MOF {[Cu
2
(6-Hmna)(6-mn)]·NH
4
}
n
(
1
, 6-Hmna = 6-mercaptonicotinic acid, 6-mn = 6-mercaptonicotinate), consisting of a two dimensional (–Cu–S–)
n
plane, is synthesized from the reaction of Cu(NO
3
)
2
, and 6,6′-dithiodinicotinic acid via the in situ cleavage of an S–S bond under hydrothermal conditions. A single crystal of the MOF is found to have a low activation energy (6 meV), small bandgap (1.34 eV) and a highest electrical conductivity (10.96 S cm
−1
) among MOFs for single crystal measurements. This approach provides an ideal roadmap for producing highly conductive MOFs with great potential for applications in batteries, thermoelectric, supercapacitors and related areas.
Metal–organic frameworks that contain metal–sulfur chains have been demonstrated to exhibit good electrical conductivity. Here, the authors integrate a 2D metal–sulfur plane into a metal–organic framework, reporting a single crystal with a high conductivity of 10.96 S/cm.
Journal Article