Hydrogen peroxide (H2O2), an accessible and eco-friendly oxidant, was employed for the template-free hydrothermal synthesis of mesoporous CeO2 based on a cerium carbonate precursor (Ce2(CO3)3•xH2O). ...Its microstructure and physicochemical properties were characterized by XRD, TEM and N2 sorption techniques. The formation of the CeO2 phase with a porous structure was strongly dependent on the presence of H2O2, while the values of the BET surface area, pore diameter and pore volume of CeO2 were generally related to the amount of H2O2 in the template-free hydrothermal synthesis. The BET surface area and pore volume of the mesoporous CeO2 synthesized hydrothermally at 180 °C with 10 mL H2O2 were 112.8 m2/g and 0.1436 cm3/g, respectively. The adsorption process had basically finished within 30 min, and the maximum adsorption efficiency within 30 min was 99.8% for the mesoporous CeO2 synthesized hydrothermally at 140 °C with 10 mL, when the initial AO7 concentration was 120 mg/L without pH preadjustment. The experimental data of AO7 adsorption were analyzed using the Langmuir and Freundlich isotherm modes. Moreover, the mesoporous CeO2 synthesized at 140 °C with 10 mL H2O2 was regenerated in successive adsorption–desorption cycles eight times without significant loss in adsorption capacity, suggesting that the as-synthesized mesoporous CeO2 in this work was suitable as an adsorbent for the efficient adsorption of AO7 dye from an aqueous solution.
In this article, we proposed a harmonic-absorbed frequency selective rasorber (HA-FSR). It consists of a non-resonant frequency selective surface (FSS) with inductive square loops, capacitive ...patches, and resistive sheet-based absorbers. The non-resonant FSS is of harmonic-suppression (HS) feature, which is free of spurious harmonic transmission bands up to three octaves of the main passband. We introduced resistive sheets on both sides of the HS-FSS to perform wideband absorption. Full-wave simulated and measured results both show that the proposed HA-FSR owns main passband with −3-dB bandwidth of 3 GHz at the <inline-formula> <tex-math notation="LaTeX">{X} </tex-math></inline-formula>-band and −10-dB absorption band from 20 to 30 GHz. The frequency range of harmonic-absorption covers from around two to three octaves of the passband. The proposed HA-FSR can be applied in electromagnetic (EM) shielding and low-observable platforms.
Superparamagnetic magnetic nanoparticles (MNPs, Fe3O4) were first synthesized based on a chemical co–precipitation method, and the core–shell magnetic silica nanoparticles (MSNPs, Fe3O4@SiO2) were ...obtained via hydrolysis and the condensation of tetraethyl orthosilicate onto Fe3O4 seed using a sol–gel process. Following that, MSNPs were immobilized using a three–step grafting strategy, where 8-hloroacetyl–aminoquinoline (CAAQ) was employed as a metal ion affinity ligand for trapping specific heavy metal ions, and a macromolecular polymer (polyethylenimine (PEI)) was selected as a bridge between the surface hydroxyl group and CAAQ to fabricate a network of organic networks onto the MSNPs’ surface. The as–synthesized MSNPs–CAAQ nanocomposites possessed abundant active functional groups and thus contained excellent removal features for heavy metal ions. Specifically, the maximum adsorption capacities at room temperature and without adjusting pH were 324.7, 306.8, and 293.3 mg/g for Fe3+, Cu2+, and Cr3+ ions, respectively, according to Langmuir linear fitting. The adsorption–desorption experiment results indicated that Na2EDTA proved to be more suitable as a desorbing agent for Cr3+ desorption on the MSNPs–CAAQ surface than HCl and HNO3. MSNPs–CAAQ exhibited a satisfactory adsorption capacity toward Cr3+ ions even after six consecutive adsorption–desorption cycles; the adsorption efficiency for Cr3+ ions was still 88.8% with 0.1 mol/L Na2EDTA as the desorbing agent. Furthermore, the MSNPs–CAAQ nanosorbent displayed a strong magnetic response with a saturated magnetization of 24.0 emu/g, and they could be easily separated from the aqueous medium under the attraction of a magnet, which could facilitate the sustainable removal of Cr3+ ions in practical applications.
Tea plant (Camellia sinensis) is an economically important beverage crop. Drought stress (DS) seriously limits the growth and development of tea plant, thus affecting crop yield and quality. To ...elucidate the molecular mechanisms of tea plant responding to DS, we performed transcriptomic analysis of tea plant during the three stages control (CK) and during DS, and recovery (RC) after DS using RNA sequencing (RNA-Seq). Totally 378.08 million high-quality trimmed reads were obtained and assembled into 59,674 unigenes, which were extensively annotated. There were 5,955 differentially expressed genes (DEGs) among the three stages. Among them, 3,948 and 1,673 DEGs were up-regulated under DS and RC, respectively. RNA-Seq data were further confirmed by qRT-PCR analysis. Genes involved in abscisic acid (ABA), ethylene, and jasmonic acid biosynthesis and signaling were generally up-regulated under DS and down-regulated during RC. Tea plant potentially used an exchange pathway for biosynthesis of indole-3-acetic acid (IAA) and salicylic acid under DS. IAA signaling was possibly decreased under DS but increased after RC. Genes encoding enzymes involved in cytokinin synthesis were up-regulated under DS, but down-regulated during RC. It seemed probable that cytokinin signaling was slightly enhanced under DS. In total, 762 and 950 protein kinases belonging to 26 families were differentially expressed during DS and RC, respectively. Overall, 547 and 604 transcription factor (TF) genes belonging to 58 families were induced in the DS vs. CK and RC vs. DS libraries, respectively. Most members of the 12 TF families were up-regulated under DS. Under DS, genes related to starch synthesis were down-regulated, while those related to starch decomposition were up-regulated. Mannitol, trehalose and sucrose synthesis-related genes were up-regulated under DS. Proline was probably mainly biosynthesized from glutamate under DS and RC. The mechanism by which ABA regulated stomatal movement under DS and RC was partly clarified. These results document the global and novel responses of tea plant during DS and RC. These data will serve as a valuable resource for drought-tolerance research and will be useful for breeding drought-resistant tea cultivars.
Marital status has long been recognized as an important prognostic factor for many cancers, however its' prognostic effect for patients with laryngeal cancer has not been fully examined. We ...retrospectively analyzed 8834 laryngeal cancer patients in the Surveillance Epidemiology and End Results database from 2004 to 2010. Patients were divided into four groups: married, widowed, single, and divorced/separated. The difference in overall survival (OS) and cancer-specific survival (CSS) of the various marital subgroups were calculated using the Kaplan-Meier curve. Multivariate Cox regression analysis screened for independent prognostic factors. Propensity score matching (PSM) was also conducted to minimize selection bias. We included 8834 eligible patients (4817 married, 894 widowed, 1732 single and 1391 divorced/separated) with laryngeal cancer. The 5-year OS and CSS of married, widowed, single, and separated/divorced patients were examined. Univariate and multivariate analyses found marital status to be an independent predictor of survival. Subgroup survival analysis showed that the OS and CSS rates in widowed patients were always the lowest in the various American Joint Committee on Cancer stages, irrespective of sex. Widowed patients demonstrated worse OS and CSS in the 1:1 matched group analysis. Among patients with laryngeal cancer, widowed patients represented the highest-risk group, with the lowest OS and CSS.
Solid-state hydrogen storage technology has emerged as a disruptive solution to the "last mile" challenge in large-scale hydrogen energy applications, garnering significant global research attention. ...This paper systematically reviews the Chinese research progress in solid-state hydrogen storage material systems, thermodynamic mechanisms, and system integration. It also quantitatively assesses the market potential of solid-state hydrogen storage across four major application scenarios: on-board hydrogen storage, hydrogen refueling stations, backup power supplies, and power grid peak shaving. Furthermore, it analyzes the bottlenecks and challenges in industrialization related to key materials, testing standards, and innovation platforms. While acknowledging that the cost and performance of solid-state hydrogen storage are not yet fully competitive, the paper highlights its unique advantages of high safety, energy density, and potentially lower costs, showing promise in new energy vehicles and distributed energy fields. Breakthroughs in new hydrogen storage materials like magnesium-based and vanadium-based materials, coupled with improved standards, specifications, and innovation mechanisms, are expected to propel solid-state hydrogen storage into a mainstream technology within 10-15 years, with a market scale exceeding USD 14.3 billion. To accelerate the leapfrog development of China's solid-state hydrogen storage industry, increased investment in basic research, focused efforts on key core technologies, and streamlining the industry chain from materials to systems are recommended. This includes addressing challenges in passenger vehicles, commercial vehicles, and hydrogen refueling stations, and building a collaborative innovation ecosystem involving government, industry, academia, research, finance, and intermediary entities to support the achievement of carbon peak and neutrality goals and foster a clean, low-carbon, safe, and efficient modern energy system.
A novel reconfigurable polarization conversion method based on a metasurface turned by PIN diodes is proposed herein. The proposed metasurface consists of one layer of a dielectric and two layers of ...metal surfaces. When the diode is in an OFF-state, a wideband linear to circular (LTC) polarization converter is realized. The results show that the metasurface can achieve LTC polarization conversion in the frequency range of 11.8-24.1 GHz, and the axial ratio (AR) reveals that the 3-dB bandwidth is approximately 68.5%. When the diode is in the ON-state, a dual-band linear to linear (LTL) polarization converter is realized, with the 3-dB bandwidths of 10.5-13.9 GHz and 17.7-27.2 GHz, achieving a polarization converter ratio (PCR) greater than 90%. The dc bias circuit of the PIN diode is etched on the reflectance surface. Therefore, no additional feeding lines are introduced, which can decrease the impact on the active metasurface; this metasurface has practical applications in microwave communication systems.
Abstract
High-index dielectric nanoparticles supporting a distinct series of Mie resonances have enabled a new class of optical antennas with unprecedented functionalities. The great wealth of ...multipolar responses has not only brought in new physical insight but also spurred practical applications. However, how to make such a colorful resonance palette actively tunable is still elusive. Here, we demonstrate that the structured phase-change alloy Ge
2
Sb
2
Te
5
(GST) can support a diverse set of multipolar Mie resonances with active tunability. By harnessing the dramatic optical contrast of GST, we realize broadband (Δ
λ
/
λ
~ 15%) mode shifting between an electric dipole resonance and an anapole state. Active control of higher-order anapoles and multimodal tuning are also investigated, which make the structured GST serve as a multispectral optical switch with high extinction contrasts (>6 dB). With all these findings, our study provides a new direction for realizing active nanophotonic devices.
The renin-angiotensin system (RAS) is the primary pathway for regulating blood pressure in the body, and angiotensin-converting enzymes (ACEs) play a crucial role in it. Hirudo nipponia is an ...invertebrate that contains a variety of active peptides; however, there are no studies on the ACE inhibitory activity of hirudo. In the present study, our aim was to identify the active peptides in hirudo based on active peptide database analysis, unexpectedly filling the gap in hirudo ACE inhibitory activity research. Prep-HPLC was used to separate the part below 3 kD from hirudo. The peptide composition of the isolates was obtained based on Orbitrap LC-MS. The activity of each group of peptides was predicted by the database and the activity was determined by bioassay. Peptides with validation activity were screened through the database. In total, 337 peptides and 18 peptides matching the NCBI leech protein database were identified. All four fractions showed ACE inhibitory activity, and the IC50 was 0.8266, 0.2708, 0.4432, and 0.1764 mg/mL, respectively. Six screened peptides showed good affinity for ACE. This work reveals for the first time that low-molecular-weight peptides from H. nipponia have ACE inhibitory activity, which can provide a new explanation for leech treatment of hypertension.
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