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1.
Oral Oncol ; 154: 106865, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823173

RESUMEN

OBJECTIVE: The aim of this study is to evaluate the efficacy and cost-effectiveness of various induction chemotherapy (IC) regimens as first-line treatment for Locoregionally advanced nasopharyngeal carcinoma (LA-NPC), aiming to provide clinicians and patients with informed insights to aid in treatment decision-making. PATIENTS AND METHODS: We conducted a network meta-analysis (NMA) and cost-effectiveness analysis (CEA) based on data from 10 clinical trials investigating IC regimens for the treatment of LA-NPC. A Bayesian NMA was performed, with the primary outcomes being hazard ratios (HRs) for disease-free survival (DFS) and overall survival (OS). To model the disease progression of LA-NPC, we developed a dynamic partitioned survival model consisting of three disease states: progression-free survival (PFS), progression disease (PD), and death. The model was run on a 3-week cycle for a research period of 10 years, with quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) serving as outcome measures. RESULTS: According to the surface under the cumulative ranking curve (SUCRA) estimates derived from the NMA, TPC and TP, as IC regimens, appear to exhibit superior efficacy compared to other treatment modalities. In terms of CEA, concurrent chemoradiotherapy (CCRT), TPF + CCRT, and GP + CCRT were found to be dominated (more costs and less QALYs). Comparatively, TPC + CCRT emerged as a cost-effective option with an ICER of $1260.57/QALY when compared to PF + CCRT. However, TP + CCRT demonstrated even greater cost-effectiveness than TPC + CCRT, with an associated increase in costs of $3300.83 and an increment of 0.1578 QALYs per patient compared to TPC + CCRT, resulting in an ICER of $20917.62/QALY. CONCLUSION: Based on considerations of efficacy and cost-effectiveness, the TP + CCRT treatment regimen may emerge as the most favorable first-line therapeutic approach for patients with LA-NPC.


Asunto(s)
Análisis Costo-Beneficio , Quimioterapia de Inducción , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Metaanálisis en Red , Humanos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/economía , Carcinoma Nasofaríngeo/mortalidad , Quimioterapia de Inducción/economía , Quimioterapia de Inducción/métodos , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/economía , Años de Vida Ajustados por Calidad de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Análisis de Costo-Efectividad
2.
J Nanobiotechnology ; 22(1): 378, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943185

RESUMEN

Tissue engineered heart valves (TEHVs) demonstrates the potential for tissue growth and remodel, offering particular benefit for pediatric patients. A significant challenge in designing functional TEHV lies in replicating the anisotropic mechanical properties of native valve leaflets. To establish a biomimetic TEHV model, we employed melt-electrowriting (MEW) technology to fabricate an anisotropic PCL scaffold. By integrating the anisotropic MEW-PCL scaffold with bioactive hydrogels (GelMA/ChsMA), we successfully crafted an elastic scaffold with tunable mechanical properties closely mirroring the structure and mechanical characteristics of natural heart valves. This scaffold not only supports the growth of valvular interstitial cells (VICs) within a 3D culture but also fosters the remodeling of extracellular matrix of VICs. The in vitro experiments demonstrated that the introduction of ChsMA improved the hemocompatibility and endothelialization of TEHV scaffold. The in vivo experiments revealed that, compared to their non-hydrogel counterparts, the PCL-GelMA/ChsMA scaffold, when implanted into SD rats, significantly suppressed immune reactions and calcification. In comparison with the PCL scaffold, the PCL-GelMA/ChsMA scaffold exhibited higher bioactivity and superior biocompatibility. The amalgamation of MEW technology and biomimetic design approaches provides a new paradigm for manufacturing scaffolds with highly controllable microstructures, biocompatibility, and anisotropic mechanical properties required for the fabrication of TEHVs.


Asunto(s)
Válvulas Cardíacas , Hidrogeles , Ratas Sprague-Dawley , Ingeniería de Tejidos , Andamios del Tejido , Ingeniería de Tejidos/métodos , Animales , Andamios del Tejido/química , Anisotropía , Ratas , Hidrogeles/química , Materiales Biocompatibles/química , Prótesis Valvulares Cardíacas , Poliésteres/química , Células Cultivadas , Humanos , Matriz Extracelular/química , Masculino
3.
Adv Sci (Weinh) ; : e2400623, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898767

RESUMEN

Solar-driven interfacial evaporation is an emerging desalination technology that can potentially relieve the freshwater scarcity issue. To obtain high and continuous evaporation rates for all-weather, chemically engineered structural materials have been widely explored for simultaneous photothermal and electrothermal conversion. However, many previously reported fabrication processes involve poor integration and considerable energy loss. Herein, a scalable photo-electro-thermal textile is proposed to enable high efficiency, long-term salt rejection, and solar-driven desalination. Specifically, the photo-electro-thermal yarns with a core (commercial electric wire)-shell (polypyrrole-decorated Tencel) structure realize the integration of electrothermal and photothermal conversion. The wrapping eccentricity of 1.53 mm and pitch of 3 T cm-1 for the electric wire are rationally regulated to achieve a high surface temperature of over 52 °C at a 3 V DC input. As a result, exceptional and stable evaporation rates of 5.57 kg m-2 h-1 (pure water) and 4.89 kg m-2 h-1 (3.5 wt.% brine) under 1 kW m-2·radiation with a 3 V input voltage are realized. Practical application shows that the textiles can achieve high water collection of over 46 kg m-2 d-1 over the whole day of operation. The constructed photo-electro-thermal textile-based evaporator provides an effective method for commercial and scalable photo-electro-thermal conversion to achieve high-performance and salt-resistant solar-driven desalination.

4.
Mater Horiz ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747363

RESUMEN

Silicon nanocrystals (SiNCs) have attracted considerable attention in many advanced applications due to silicon's high natural abundance, low toxicity, and impressive optical properties. However, little attention has been paid to fluorescence anti-counterfeiting applications based on lipophilic silicon nanocrystals. Moreover, it is also a challenge to fabricate aging-resistant anti-counterfeiting coatings based on silicon nanocrystals. Herein, this paper presents a demonstration of aging-resistant fluorescent anti-counterfeiting coatings based on red fluorescent silicon nanocrystals. In this work, lipophilic silicon nanocrystals (De-SiNCs) with red fluorescence were prepared first by thermal hydrosilylation between hydrogen-terminated silicon nanocrystals (H-SiNCs) and 1-decene. Subsequently, a new SiNCs/PDMS coating (De-SiNCs/DV) was fabricated by dispersing De-SiNCs into reinforcing PDMS composites with vinyl-capped silicone resin. Interestingly, the De-SiNCs/DV composites exhibit superior transparency (up to 85%) in the visible light range, outstanding fluorescence stabilities with an average lifetime of 20.59 µs under various conditions including acidic/alkaline environments, different organic solvents, high-humidity environments and UV irradiation. Meanwhile, the encapsulation of De-SiNCs is beneficial to enhancing the mechanical properties and thermal stability of De-SiNCs/DV composites. Additionally, the De-SiNCs/DV coating exhibits an excellent anti-counterfeiting effect on cotton fabrics when used as an ink in screen-printing. These findings pave the way for developing innovative flexible multifunctional anti-counterfeiting coatings in the future.

5.
Cancer Control ; 31: 10732748241255535, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38773761

RESUMEN

The current standard treatment for locally advanced squamous cell carcinoma of the head and neck (LASCCHN) comprises concurrent radiotherapy (CRT) alongside platinum-based chemotherapy. However, innovative therapeutic alternatives are being evaluated in phase II/III randomized trials. This study employed a Bayesian network meta-analysis (NMA) using fixed effects to provide both direct and indirect comparisons of all existing treatment modalities for unresectable LASCCHN. METHODS: We referenced randomized controlled trials (RCTs) from January 2000 to July 2023 by extensively reviewing PubMed, EMBASE, and Web of Science databases, adhering to the Cochrane methodology. Relevant data, including summary estimates of overall survival (OS) and progression-free survival (PFS), were extracted from these selected studies and recorded in a predefined database sheet. Subsequently, we conducted a random effects network meta-analysis using a Bayesian framework. RESULTS: Based on the Surface Under the Cumulative Ranking (SUCRA) values, the league table organizes the various treatments for OS in the following order: IC + RT&MTT, MTT-CRT, IC + CRT&MTT, CRT, IC + CRT, MTT-RT, IC + MTT-RT, and RT. In a similar order, the treatments rank as follows according to the league table: IC + CRT&MTT, MTT-CRT, IC + CRT, IC + RT&MTT, CRT, IC + MTT-RT, MTT-RT, and RT. Notably, none of these treatments showed significant advantages over concurrent chemoradiotherapy. CONCLUSION: Despite concurrent chemoradiotherapy being the prevailing treatment for LASCCHN, our findings suggest the potential for improved outcomes when concurrent chemoradiotherapy is combined with targeted therapy or induction chemotherapy.


The current standard treatment for advanced head and neck cancer involves combining radiation therapy with chemotherapy. However, there are ongoing trials exploring alternative therapies. In this study, we conducted a comprehensive analysis of existing treatments using a statistical method called network meta-analysis. Our analysis included data from randomized controlled trials published between January 2000 and July 2023. We focused on overall survival and progression-free survival as key outcome measures. The results of our analysis showed that none of the alternative treatments demonstrated significant advantages over the standard concurrent chemoradiotherapy. Nevertheless, there is potential for improved outcomes when targeted therapy or induction chemotherapy is combined with concurrent chemoradiotherapy.


Asunto(s)
Neoplasias de Cabeza y Cuello , Metaanálisis en Red , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Quimioradioterapia/métodos , Teorema de Bayes , Ensayos Clínicos Controlados Aleatorios como Asunto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
6.
ACS Nano ; 18(23): 15312-15325, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38809601

RESUMEN

The exceptional biocompatibility and adaptability of hydrogels have garnered significant interest in the biomedical field for the fabrication of biomedical devices. However, conventional synthetic hydrogels still exhibit relatively weak and fragile properties. Drawing inspiration from the photosynthesis process, we developed a facile approach to achieve a harmonious combination of superior mechanical properties and efficient preparation of silk fibroin hydrogel through photo-cross-linking technology, accomplished within 60 s. The utilization of riboflavin and H2O2 enabled a sustainable cyclic photo-cross-linking reaction, facilitating the transformation from tyrosine to dityrosine and ultimately contributing to the formation of highly cross-linked hydrogels. These photo-cross-linking hydrogels exhibited excellent elasticity and restorability even after undergoing 1000 cycles of compression. Importantly, our findings presented that hydrogel-encapsulated adipose stem cells possess the ability to stimulate cell proliferation along with stem cell stemness. This was evidenced by the continuous high expression levels of OCT4 and SOX2 over 21 days. Additionally, the utilization of photo-cross-linking hydrogels can be extended to various material molding platforms, including microneedles, microcarriers, and bone screws. Consequently, this study offered a significant approach to fabricating biomedical hydrogels capable of facilitating real-time cell delivery, thereby introducing an innovative avenue for designing silk devices with exceptional machinability and adaptability in biomedical applications.


Asunto(s)
Proliferación Celular , Hidrogeles , Hidrogeles/química , Hidrogeles/farmacología , Hidrogeles/síntesis química , Proliferación Celular/efectos de los fármacos , Fibroínas/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Animales , Reactivos de Enlaces Cruzados/química , Seda/química , Procesos Fotoquímicos , Células Madre/citología , Células Madre/metabolismo , Células Madre/efectos de los fármacos , Riboflavina/química , Riboflavina/farmacología , Bombyx , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/farmacología , Humanos
7.
Int J Biol Macromol ; 270(Pt 2): 132462, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38772470

RESUMEN

Rapid development of society and the improvement of people's living standards have stimulated people's keen interest in fashion clothing. This trend has led to the acceleration of new product innovation and the shortening of the lifespan for cotton fabrics, which has resulting in the accumulation of waste cotton textiles. Although cotton fibers can be degraded naturally, direct disposal not only causes a serious resource waste, but also brings serious environmental problems. Hence, it is significant to explore a cleaner and greener waste textile treatment method in the context of green and sustainable development. To realize the high-value utilization of cellulose II aerogel derived from waste cotton products, great efforts have been made and considerable progress has been achieved in the past few decades. However, few reviews systematically summarize the research progress and future challenges of preparing high-value-added regenerated cellulose aerogels via dissolving cotton and other cellulose wastes. Therefore, this article reviews the regenerated cellulose aerogels obtained through solvent methods, summarizes their structure, preparation strategies and application, aimed to promote the development of the waste textile industry and contributed to the realization of carbon neutrality.


Asunto(s)
Celulosa , Fibra de Algodón , Geles , Textiles , Celulosa/química , Fibra de Algodón/análisis , Geles/química
8.
Proc Natl Acad Sci U S A ; 121(22): e2317205121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38776369

RESUMEN

Understanding the operando defect-tuning performance of catalysts is critical to establish an accurate structure-activity relationship of a catalyst. Here, with the tool of single-molecule super-resolution fluorescence microscopy, by imaging intermediate CO formation/oxidation during the methanol oxidation reaction process on individual defective Pt nanotubes, we reveal that the fresh Pt ends with more defects are more active and anti-CO poisoning than fresh center areas with less defects, while such difference could be reversed after catalysis-induced step-by-step creation of more defects on the Pt surface. Further experimental results reveal an operando volcano relationship between the catalytic performance (activity and anti-CO ability) and the fine-tuned defect density. Systematic DFT calculations indicate that such an operando volcano relationship could be attributed to the defect-dependent transition state free energy and the accelerated surface reconstructing of defects or Pt-atom moving driven by the adsorption of the CO intermediate. These insights deepen our understanding to the operando defect-driven catalysis at single-molecule and subparticle level, which is able to help the design of highly efficient defect-based catalysts.

9.
Heredity (Edinb) ; 133(1): 11-20, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38822132

RESUMEN

Genome-wide association study (GWAS) is a powerful tool to identify genomic loci underlying complex traits. However, the application in natural populations comes with challenges, especially power loss due to population stratification. Here, we introduce a bivariate analysis approach to a GWAS dataset of Arabidopsis thaliana. We demonstrate the efficiency of dual-phenotype analysis to uncover hidden genetic loci masked by population structure via a series of simulations. In real data analysis, a common allele, strongly confounded with population structure, is discovered to be associated with late flowering and slow maturation of the plant. The discovered genetic effect on flowering time is further replicated in independent datasets. Using Mendelian randomization analysis based on summary statistics from our GWAS and expression QTL scans, we predicted and replicated a candidate gene AT1G11560 that potentially causes this association. Further analysis indicates that this locus is co-selected with flowering-time-related genes. The discovered pleiotropic genotype-phenotype map provides new insights into understanding the genetic correlation of complex traits.


Asunto(s)
Arabidopsis , Flores , Estudio de Asociación del Genoma Completo , Fenotipo , Sitios de Carácter Cuantitativo , Arabidopsis/genética , Estudio de Asociación del Genoma Completo/métodos , Flores/genética , Polimorfismo de Nucleótido Simple , Genotipo , Modelos Genéticos , Genética de Población , Simulación por Computador , Alelos , Genoma de Planta , Análisis de la Aleatorización Mendeliana
10.
ACS Sens ; 9(5): 2575-2584, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38695880

RESUMEN

Although electronic textiles that can detect external stimuli show great promise for fire rescue, existing firefighting clothing is still scarce for simultaneously integrating reliable early fire warning and real-time motion sensing, hardly providing intelligent personal protection under complex high-temperature conditions. Herein, we introduce an "all-in-one" hierarchically sandwiched fabric (HSF) sensor with a simultaneous temperature and pressure stimulus response for developing intelligent personal protection. A cross-arranged structure design has been proposed to tackle the serious mutual interference challenge during multimode sensing using two separate sets of core-sheath composite yarns and arrayed graphene-coated aerogels. The functional design of the HSF sensor not only possesses wide-range temperature sensing from 25 to 400 °C without pressure disturbance but also enables highly sensitive pressure response with good thermal adaptability (up to 400 °C) and wide pressure detection range (up to 120 kPa). As a proof of concept, we integrate large-scalable HSF sensors onto conventional firefighting clothing for passive/active fire warning and also detecting spatial pressure and temperature distribution when a firefighter is exposed to high-temperature flames, which may provide a useful design strategy for the application of intelligent firefighting protective clothing.


Asunto(s)
Presión , Temperatura , Textiles , Textiles/análisis , Humanos , Incendios , Bomberos , Ropa de Protección , Grafito/química , Dispositivos Electrónicos Vestibles
12.
Int J Biol Macromol ; 268(Pt 1): 131622, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636762

RESUMEN

Separator is an essential component of lithium-ion batteries (LIBs), which is placed between the electrodes to impede their electrical contact and provide the transport channels for lithium ions. Traditionally, the separator contributes the overall mass of LIBs, thereby reducing the gravimetric capacity of the devices. Herein, a dual-layer redox-active cellulose separator is designed and fabricated to enhance the electrochemical performances of LIBs by introducing NiS. The presented separator is composed of an insulating bacterial cellulose (BC) nanofiber layer and a conductive, and redox-active NiS@BC/carbon nanotubes layer. By using the NiS@BC separator, the discharge capacity of the LiFePO4//Li half battery is enhanced to 117 mAh g-1 at a current of 2C owing to the redox-activity of NiS. Moreover, the functional separator-electrode interface can facilitate the homogenous Li stripping/plating and depress the polarization upon the repeated stripping/plating process. Consequently, the battery containing the redox-active separator exhibits outstanding cycle stability and rate capability. The present study contributes a novel strategy for the developments of functional separators to improve the electrochemical properties of LIBs.


Asunto(s)
Celulosa , Suministros de Energía Eléctrica , Electrodos , Litio , Nanofibras , Oxidación-Reducción , Litio/química , Nanofibras/química , Celulosa/química , Celulosa/análogos & derivados , Nanotubos de Carbono/química , Iones/química , Técnicas Electroquímicas
13.
Nat Commun ; 15(1): 1979, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438379

RESUMEN

Carbon fibers (CFs) have attracted attention in the automotive, aviation, and aerospace industries. However, the coloration of CFs is challenging due to their brittleness, inertness, complexity, and time/energy-intensive processes. Herein, inspired by the naturally grown protrusive nanostructures on the green central surface of peacock back feathers, we report an in-situ self-growing strategy for developing carbon spheres (CSs) on the CFs surface to achieve color tuning. This is achieved via the dynamic growth of CSs using glucose as the feeding material. Combined with the coloration process, the interaction between CSs and CFs promotes stable interfacial forces in integrated molding. This strategy allows the coloring system to continuously vary its color in a designated manner, thereby, endowing it with satisfactory mechanical robustness, acid durability, and light fastness. We anticipate this developed approach can be potentially competitive in the color construction of CFs with multi-colors due to its low-cost manufacturing.

14.
Polymers (Basel) ; 16(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38543399

RESUMEN

The global increase in population, the phenomenon of climate change, the issue of water pollution and contamination, and the inadequate management of water resources all exert heightened strain on freshwater reserves. The potential utilization of the interfacial solar steam generation (ISSG) system, which utilizes photothermal conversion to generate heat on material surfaces for wastewater purification and desalination purposes, has been successfully demonstrated. Textile-material-based ISSG devices, including (woven, nonwoven, and knitted) fabrics and electrospinning membranes, exhibit distinct properties such as a rough surface texture, high porosity, significant surface area, exceptional flexibility, and robust mechanical strength. These characteristics, combined with their affordability, accessibility, and economic viability for widespread implementation, make them extremely attractive for applications in SSG. In this review, a comprehensive analysis of the emerging concepts, advancements, and applications of textile materials, such as woven, nonwoven, and knitted fabrics and electrospun membranes, in ISSG for wastewater purification and desalination is presented. We also emphasize significant obstacles and potential prospects in both theoretical investigations and real-world implementations, aiming to contribute to future advancements in the domain of textile-material-based interfacial evaporation in wastewater purification and desalination. Furthermore, the drawbacks and the challenges of ISSG systems are also highlighted.

15.
Int J Biol Macromol ; 264(Pt 2): 130779, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38471604

RESUMEN

Regenerated cellulose fibers has attracted increasing attention for high-grade textile raw materials and industrial textiles, but the low mechanical property caused by differences in regenerated raw materials and production levels limits its commercial application in the product diversity. Herein, we proposed a novel triple-crosslinking strategy by coupling with hydrogen bonds, chemical crosslinking, and internal mineralization from multiple pulsed vapor phase infiltration (MPI) to improve the mechanical performance of regenerated cellulose fibers. A binary solvent composed of ionic liquid (IL) and dimethyl sulfoxide (DMSO) is used to dissolve waste cotton textile and then wet spinning. Dual-crosslinking is firstly achieved by coupling glutaraldehyde (GA) and cellulose reaction. Subsequently, a metal oxide is intentionally infiltrated into inner cellulosic through MPI technology to form a third form of crosslinking, accompanied by the ultra-thin metal oxide nano-layer onto the surface of regenerated cellulose fibers. Results showed that the triple-crosslinking strategy has increased the tensile stress of the fiber by 43.57 % to 287.03 MPa. In all, triple-crosslinking strategy provides a theoretical basis and technical approach for the reinforcement of weak fibers in waste cotton recycling, which is expected to accelerate the development of the waste textile recycling industry and promote of the added-value of regenerated products.


Asunto(s)
Fibra de Algodón , Textiles , Celulosa/química , Óxidos
16.
Sensors (Basel) ; 24(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38475085

RESUMEN

Sensor degradation and failure often undermine users' confidence in adopting a new data-driven decision-making model, especially in risk-sensitive scenarios. A risk assessment framework tailored to classification algorithms is introduced to evaluate the decision-making risks arising from sensor degradation and failures in such scenarios. The framework encompasses various steps, including on-site fault-free data collection, sensor failure data collection, fault data generation, simulated data-driven decision-making, risk identification, quantitative risk assessment, and risk prediction. Leveraging this risk assessment framework, users can evaluate the potential risks of decision errors under the current data collection status. Before model adoption, ranking risk sensitivity to sensor data provides a basis for optimizing data collection. During the use of decision algorithms, considering the expected lifespan of sensors enables the prediction of potential risks the system might face, offering comprehensive information for sensor maintenance. This method has been validated through a case study involving an access control.

17.
Angew Chem Int Ed Engl ; 63(20): e202402086, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477869

RESUMEN

Combining a strong second-order nonlinear optical (NLO) effect (>1×KH2PO4 (KDP)), a large band gap (>4.2 eV), and a moderate birefringence in ultraviolet (UV) NLO crystals remains a formidable challenge. Herein, Cd(SCN)2(C4H6N2)2, the first example of a thiocyanate capable of realizing a phase-matched UV NLO crystal material, is obtained by reducing the sulfur (S) content in the centrosymmetric (CS) structure of Cd(SCN)2(CH4N2S)2. Compared to the "shoulder-to-shoulder" one-dimensional (1D) chain of Cd(SCN)2(CH4N2S)2, Cd(SCN)2(C4H6N2)2 has a different sawtooth 1D chain structure. Cd(SCN)2(CH4N2S)2 has second harmonic generation (SHG) inertia with a band gap of 3.90 eV and a UV cutoff edge of 342 nm, however, it possesses a large birefringence (0.35@546 nm). In contrast, the symmetry center breaking of Cd(SCN)2(C4H6N2)2 leads to remarkably strong SHG intensity (10 times that of KDP). Furthermore, it has a wide band gap (4.74 eV), short UV cutoff edge (234 nm), and moderate birefringence capable of phase matching (0.17@546 nm). This research indicates that thiocyanates are a promising class of UV NLO crystal materials, and that modulation of the sulfur content of CS thiocyanates is an effective strategy for the development of UV NLO crystals with excellent overall performances.

18.
Ultrason Sonochem ; 104: 106837, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38429167

RESUMEN

The vibration mode of the radiation surface of transducer (or structure of supersaturated cavitation cloud in thin liquid) is investigated experimentally by high-speed photography. The classification of saturated, supersaturated and undersaturated cavitation clouds was proposed, and a comparison was made between saturated and supersaturated cavitation cloud structures in liquid thin layers. The characteristics and formation mechanism of supersaturated cavitation cloud structure were investigated. Based on the close correspondence and rapid response between the distribution of supersaturated cavitation clouds and vibration modes of radiation surface, a new approach is proposed to measure the vibration mode of transducer operating at high power and large amplitude in real time.

20.
Ultrason Sonochem ; 103: 106791, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38325060

RESUMEN

The phenomenon of cavitation within tubes is a common scenario in the fields of medicine and industry. This paper focuses on the effects of rigid circular tube length, diameter and the distance of bubble - tube port on the behavior of bubble in tube. The low-voltage discharge technique was utilized to induce a cavitation bubble in deionized water. The effects of rigid tube lengths, diameters, and bubble-tube port distances on the morphology of bubbles are observed using high-speed camera. It has been found that as the length of the rigid tube increases, so does the period, and this effect is more pronounced in tubes with smaller diameters. Conversely, the cavitation bubble period decreased and then stabilized as the tube diameter increased, the ratio of tube radius and the bubble radius exceeds 4.8, the period of bubble in tube is similar to that of bubble in free field. Further analysis of the influence of tube characteristics on microjets reveals that a pair of oppositely microjets were formed along the tube axis by the bubble near the midpoint of the tube axis. Moreover, when the non-dimensional tube length η < 3.5, the increase tube diameter results in a decrease microjet velocity. It has also been observed that as the bubble gradually approaches the interior of the tube, the velocity of microjets directed inward decreases. Additionally, the smaller the diameter of the tube, the greater the bubble-tube port distance required for the microjets to reach the same level of velocity as bubble near the center of the tube axis. These findings hold theoretical implications for improvement of targeted drug delivery efficiency in medicine and enhance the operational efficiency of inertial micropumps in industries.

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