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This work reports six new full-dimensional adiabatic potential energy surfaces (PESs) of the N3 system (four 4Aâ³ states and two 2Aâ³ states) at the MRCI + Q/AVQZ level of theory that correlated to N2(X1Σg+) + N(4S), N2(X1Σg+) + N(2D), N2(A3Σu+) + N(4S), N2(B3Πg) + N(4S), N2(W3Δu) + N(4S), and N(4S) + N(4S) + N(4S) channels. The neural networks with a proper account of the nuclear permutation invariant symmetry of N3 were employed to fit the PESs based on about 4000 ab initio points. The accuracy of the PESs was validated by excellent agreement on the equilibrium bond length, vertical excitation energy, and dissociation energy with experimental values. Two possible mechanisms of the formation of N2(A) were found. One is that the collision occurs between N2(X) and N(4S) in the 14Aâ³ state, followed by a nonadiabatic transition through the conical intersection with the 24Aâ³ PES, resulting in the formation of the N2(A) + N(4S) product. The other takes place in the collision among three N(4S) atoms in the adiabatic 24Aâ³ state, and then, N2(A) + N(4S) is formed. This is the first systematical research of the N3 system focusing on the formation of the excited states of N2 via both adiabatic and nonadiabatic pathways.
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We theoretically investigate the coherent control of strong-field high-harmonic generation in the presence of an isolated attosecond pulse. It is found that the rapid modulation of the controlled signal exhibits interference fringe structures in the delay-dependent spectra. By comparing the classical trajectory model with quantum mechanical calculation, it is demonstrated that the fringes are resulted from the interference between the photon- and the tunnelling-initiated recombination pathways. The relative recombination times for the two paths are reconstructed from the interference fringes, which provides a novel scheme for optical observation of the interplay of the photionization and tunneling ionization electron dynamics in attosecond resolution.
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In this work, a user-friendly chitin-based adsorbent (CT-PmPD) was synthesized by in-situ polymerization of m-phenylenediamine on chitin bead, which could effectively remove Cr(VI) from water. The structure and morphology of the CT-PmPD were characterized by FT-IR, XRD, SEM, zeta potential and XPS. Specifically, the effect of adsorbed dosage, pH, contact time, adsorption temperature and coexisting salt on the adsorption of Cr(VI) were studied. Besides, the adsorption mechanism of CT-PmPD toward Cr(VI) were also analyzed. Consequently, CT-PmPD exhibited a monolayer adsorption and the Langmuir model fitted a Cr(VI) adsorption capacity reaching 185.4 mg/g at 298 K. The high adsorption capacity was attributed to the abundant amino groups of CT-PmPD, which could be protonated to boost the electrostatic attraction of Cr(VI) oxyanions, thus providing electron to reduce Cr(VI). Additionally, the CT-PmPD revealed a good regeneration and reusability capacity, maintaining most of its adsorption capacity even after five cycles of adsorption-desorption. This high adsorption capacity and excellent regeneration performance highlighted the great potential of CT-PmPD for the removal of Cr(VI).
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Quitina , Poluentes Químicos da Água/análise , Adsorção , Cromo , Cinética , Fenilenodiaminas , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Developing environmentally friendly film materials for packaging pesticides is significant yet challenging. The use of native starch for preparing inner packaging materials of pesticides is limited by its physicochemical properties. In this study, a novel strategy of synergetic mechanical activation (MA)-enhanced solid-phase esterification of starch and cooperative combination of starch and polyvinyl alcohol (PVA) was proposed to fabricate biodegradable and cold-water-soluble starch (St)/PVA films. The appropriate esterification of starch and favorable compatibility between starch and PVA contributed to the production of St/PVA films by the extrusion-blowing method. The as-prepared film with St/PVA ratio of 4:6 exhibited outstanding mechanical properties (tensile strengths of 21.0 MPa; elongation at break of 213.9 %), cold-water solubility (dissolution time of 90 s), and oxygen barrier performance (oxygen transmission rate of 1.41 cm3/(m2·day·bar)). The dissolved St/PVA films with amphiphilic groups were conducive to the emulsification of butachlor (a fat-soluble liquid pesticide) and the dispersibility of oxyfluorfen (a fat-soluble solid pesticide). Furthermore, a mechanism of the interaction between pesticides and the surface of weed leaves was proposed to reveal the enhanced efficacy of St/PVA films-packaged pesticides. The strategy based on MA-enhanced esterification and PVA blending is efficient to produce starch-based films suitable for inner packaging materials of pesticides.
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The production of high-performance starch-based packaging films by extrusion blowing is challenging, ascribed to poor processability of the blend precursors. In this study, a new strategy of mechanical activation (MA)-enhanced metal-organic coordination was proposed to improve the processability of starch (St)/polyvinyl alcohol (PVA) blend precursor, with calcium acetate (CA) as a chelating agent and glycerol as a plasticizer. MA pretreatment activated the hydroxyl groups of starch and PVA for constructing strong metal-organic coordination between CA and St/PVA during reactive extrusion, which effectively enhanced the melt processing properties of the blend precursor, contributing to the fabrication of high-performance St/PVA films by the extrusion-blowing method. The as-prepared St/PVA films exhibited excellent mechanical properties (tensile strength of 34.5 MPa; elongation at break of 271.8 %), water vapor barrier performance (water vapor permeability of 0.704 × 10-12 g·cm-1·s-1·Pa-1), and oxygen barrier performance (oxygen transmission rate of 0.7 cm3/(m2·day·bar)), along with high transmittance and good uniformity. These outstanding characteristics and performances can be attributed to the improved interfacial interaction and compatibility between the two matrix phases. This study uncovers the mechanism of MA-enhanced metal-organic coordination for improving the properties of starch-based films, which provides a convenient and eco-friendly technology for the preparation of high-performance biodegradable films.
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The treatment of emulsion wastewater poses significant challenges. In this study, a novel porous material, namely esterified bagasse/poly(N, N-dimethylacrylamide)/sodium alginate (SBS/PDMAA/Alg) aerogel, was developed for efficient demulsification and oil recovery. By grafting a poly(N-isopropylacrylamide) (PNIPAM) brush onto the SBS/PDMAA/Alg skeleton through free radical polymerization, the resulting aerogel exhibits both surface charge and a molecular brush structure. The aerogel demonstrates remarkable demulsification efficiency for cationic surfactant-stabilized emulsions at various concentrations, achieving a demulsification efficiency of 95.6% even at an oil content of 100 g L-1. Furthermore, the molecular brush structure extends the application range of the aerogel, enabling a demulsification efficiency of 98.3% for anionic and non-ionic surfactant-stabilized emulsions. The interpenetrating polymer network (IPN) structure formed by SBS, PDMAA, and alginate enhances the mechanical stability of the aerogel, enabling a demulsification efficiency of 91.3% even after 20 repeated cycles. The demulsification ability of the composite aerogel is attributed to its surface charge, high interfacial activity, and unique brush-like structure. A demulsification mechanism based on the synergistic effect of surface charge and molecular brush is proposed to elucidate the efficient demulsification process.
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A novel starch-based model dough used to exploit staple foods was demonstrated to be feasible, which was based on damaged cassava starch (DCS) obtained by mechanical activation (MA). This study focused on the retrogradation behavior of starch dough and the feasibility of its application in functional gluten-free noodles. Starch retrogradation behavior was investigated by low field-nuclear magnetic resonance (LF-NMR), X-ray diffraction (XRD), scanning electron microscope (SEM), texture profile and resistant starch (RS) content analysis. During starch retrogradation, water migration, starch recrystallization and microstructure changes were observed. Short-term retrogradation could significantly alter the texture properties of starch dough, and long-term retrogradation promoted the formation of RS. The damage level influenced starch retrogradation, and damaged starch with the increasing damage level was beneficial to facilitate the starch retrogradation. Gluten-free noodles made from the retrograded starch had acceptable sensory quality, with darker color and better viscoelasticity than Udon noodles. This work provides a novel strategy for the proper utilization of starch retrogradation for the development of functional foods.
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Manihot , Amido , Amido/química , Manihot/química , Alimentos , Armazenamento de Alimentos , ViscosidadeRESUMO
Starch-fatty acid complexes used as emulsifiers have caught great attention because of their renewability and excellent emulsifying property, the development of a simple and efficient synthesis method for the fabrication of starch-fatty acid complexes is still greatly challenging. Herein, the rice starch-fatty acid complexes (NRS-FA) were successfully prepared by mechanical activation method using different long chain fatty acids (myristic acid, palmitic acid, and stearic acid) and native rice starch (NRS) as the raw materials. The results showed that the prepared NRS-FA with a V-shaped crystalline structure exhibited a higher digestion resistance than NRS. Moreover, when the chain length of fatty acids increased from 14 to 18 carbons, the contact angle of the complexes was much closer to 90°, and the average particle size was smaller, deriving the better emulsifying property of NRS-FA18 complexes, which were suitable to be used as an emulsifier to stabilize curcumin-loaded Pickering emulsions. The results of storage stability and in vitro digestion showed that the curcumin retention could reach 79.4 % after 28 days of storage and 80.8 % of curcumin was retained in the system after simulated gastric digestion, showing good encapsulation and delivery performance of prepared Pickering emulsions, which attributed to the enhancement of the coverage of particles at the oil-water interface.
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Curcumina , Amido , Emulsões/química , Amido/química , Curcumina/química , Ácidos Graxos , Técnicas de Síntese em Fase Sólida , Emulsificantes/químicaRESUMO
Herein, a novel superdispersed calcium borate@polydopamine/cellulose acetate-laurate nanocomposite (CTAB-CB@PDA/CAL) is successfully synthesized by a double-template-regulated biomimetic mineralization strategy using PDA/CAL as a hard template and cetyltrimethylammonium bromide (CTAB) as a soft template and surface hydrophobic modifier. The results show that CB can grow uniformly on the CAL surface, and CTAB can improve the hydrophobicity of CTAB-CB@PDA/CAL due to the synergistic effect of the double templates, which contributes to the enhanced dispersibility and long-term dispersion stability of CTAB-CB@PDA/CAL in poly-alpha-olefin (PAO) base oil. Furthermore, CB can rapidly enter the friction interface due to the long substituents of CTAB and CAL, so CTAB-CB@PDA/CAL used as a lubricant additive in PAO base oil exhibits superior tribological performance compared to CB, CB/CAL, and CB@PDA/CAL.
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Lauratos , Nanocompostos , Cetrimônio , Biomimética , Nanocompostos/químicaRESUMO
The development of sustainable catalysts for the efficient conversion of biomass to desirable chemicals is significant and challenging. Herein, a stable biochar (BC)-supported amorphous aluminum solid acid catalyst with Brønsted-Lewis dual acid sites was constructed through one-step calcination of a mechanical activation (MA)-treated precursor (starch, urea, and Al(NO3)3). The as-prepared N-doped BC (N-BC)-supported Al composite (MA-Al/N-BC) was used for the selective catalytic conversion of cellulose to produce levulinic acid (LA). MA treatment promoted uniform dispersion and stable embedding of Al-based components in the N-BC support with nitrogen- and oxygen-containing functional groups. This process provided the MA-Al/N-BC catalyst with Brønsted-Lewis dual acid sites and improved its stability and recoverability. When the MA-Al/N-BC catalyst was used under optimal reaction conditions (180 °C, 4 h), it achieved a cellulose conversion rate of 93.1% and a LA yield of 70.1%. Additionally, it also showed high activity for catalytic conversion of other carbohydrates. The results of this study offer a promising solution for the production of sustainable biomass-derived chemicals through the use of stable and eco-friendly catalysts.
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Alumínio , Celulose , Ácidos de Lewis , Carboidratos , CatáliseRESUMO
Sulfate radicals-based Fenton-like technology has placed more emphasis on effectively dealing with the threat of dye wastewater. In this work, the Zn-doped CuFe2O4@biochar composite (Cu0.9Zn0.1Fe2O4@BC) was prepared through the convenient sol-gel pyrolysis process and applied as heterogeneous persulfate (PS) activator for crystal violet (CV) degradation. The crystal morphology and physicochemical properties of Cu0.9Zn0.1Fe2O4@BC were investigated by scanning electron microscope (SEM), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), Brunauer-Emmett-Teller method (BET), and X-ray photoelectron spectroscopy (XPS). The morphology of the catalyst changed before and after Zn doping. The crystallite size, lattice constant, saturation magnetization, and oxygen vacancy content increased after doping Zn. Compared with CuFe2O4@BC, the CV degradation efficiency of Cu0.9Zn0.1Fe2O4@BC activating PS increased from 87.7 to 96.9%, and the corresponding reaction rate constant increased by about 3.69 times. The effect of experimental conditions was systematically studied on the degradation progress. The degradation efficiency of CV was 91% after five times cycle experiments. Multiple experiments indicated that SO4â¢-, â¢OH and O2â¢- predominated for CV degradation. The degradation mechanism of CV in the Cu0.9Zn0.1Fe2O4@BC/PS system involved both free radical (SO4â¢-, â¢OH and O2â¢-) and non-free radical pathways (electron transfer). The possible degradation pathways were investigated according to the ultra-performance liquid chromatography mass spectrometry (UPLC-MS) analysis of degradation intermediates. The result showed that Cu0.9Zn0.1Fe2O4@BC have an excellent catalyst performance, which provides a new strategy for improving catalytic activity.
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Violeta Genciana , Zinco , Cromatografia Líquida , Espectrometria de Massas em Tandem , Carvão Vegetal/químicaRESUMO
Background: Grading based on histopathologic indicators cannot accurately assess the prognosis of phyllodes tumor (PT) of the breast. This article aimed to investigate the correlation between PT prognosis and clinicopathological features, treatment, and surgical margin. Methods: The clinicopathological data of patients with pathologically confirmed PT at our institution were retrospectively collected. Univariate and multivariate Cox proportional risk models were employed to test the effects of different variables on the prognosis of PT. A nomogram to predict the 1-, 3-, 5-, and 10-year recurrence-free survival (RFS) of PT was proposed, and its discriminative ability and calibration were tested using the concordance index (C-index), area under the curve (AUC), and calibration plots. All statistical analyses were performed using R. Results: A total of 342 PT patients were included, including 242 benign (70.8%), 75 borderline (21.9%) and 25 malignant (7.3%) cases. The median follow-up period was 64.5 months (range, 3-179 months), 66 PT patients had local recurrence (LR), and four patients had distant metastasis. The 1-, 3-, 5-, and 10-year RFS of the PT patients were 90.8%, 81.8%, 78%, and 76.7%, respectively. Age, fibroadenoma (FA) surgery history, treatment, mitotic activity, and surgical margin were selected as the independent factors for PT prognosis. The nomogram showed good discriminative ability and calibration, as indicated by the C-index [0.78, 95% confidence interval (CI): 0.75-0.11]. Conclusions: Independent predictors related to PT prognosis were selected to establish a nomogram for predicting the RFS of PT. This nomogram was able to objectively stratify PT patients into prognostic groups and performed well in the internal validation.
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This study aimed to produce bio-based levulinic acid (LA) via direct and efficient conversion of cellulose catalyzed by a sustainable solid acid. A carbon foam (CF)-supported aluminotungstic acid (HAlW/CF) catalyst with Brønsted-Lewis dual-acidic sites was creatively engineered by a hydrothermal impregnation method. The activity of the HAlW/CF catalyst was determined via the hydrolysis and conversion of cellulose to prepare LA in aqueous system. The cooperative effect of Brønsted and Lewis acids in HAlW/CF resulted in high cellulose conversion (89.4%) and LA yield (60.9%) at 180 °C for 4 h, which were greater than the combined catalytic efficiencies of single HAlW and CF under the same conditions. The HAlW/CF catalyst in block form exhibited superior catalytic activity, facile separation from reaction system, and favorable reusability. This work offers novel perspectives for the development of recyclable dual-acidic catalysts to achieve one-pot catalytic conversion of biomass to value-added chemicals.
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Celulose , Ácidos de Lewis , Carbono , Ácidos Levulínicos , CatáliseRESUMO
Although the core-shell structure magnetic nanocomposites have been widely used as lubricant additives, their tribological properties are still poor under high temperature and high load. Herein, the graphitized C/Fe3O4 magnetic nanocomposites (g-C/Fe3O4) with an interpenetrating network structure were successfully fabricated by an in situ hydrothermal carbonization method combined with a subsequent ball milling process at room temperature. The results showed that the ball milling process not only promoted the transformation of graphitized carbon but also effectively eliminated the interfacial effect between carbon and Fe3O4. Moreover, the g-C/Fe3O4 used as a lubricant additive in rapeseed oil exhibited excellent tribological properties and high thermo-stability under 155 °C and 980 N, with the friction coefficient reduced by 32.8% compared to the independent Fe3O4. The enhanced tribological performance of g-C/Fe3O4 could be attributed to the graphitized carbon and its interpenetrating network structure under low load force (392 N), while under high load force (980 N), it could be ascribed to the synergistic effect between the graphitized carbon and magnetic Fe3O4 nanoparticles. This work not only offers a method for the synthesis of nanocomposite lubricant additives but also shows great potential in practical applications for high-temperature tribology.
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Background: Information is still controversial in the studies regarding the current optimal surgical management of phyllodes tumors (PTs) of the breast. Local recurrence (LR) may occur with an upgraded in the pathological grade, influencing the prognosis of patients with PT. This systematic review and meta-analysis aimed to investigate the association of LR risk with margin status and margin width which could have significant implications on the surgical management of PT. Methods: Independent and comprehensive searches were performed by two authors through five databases including PubMed, Medline, Embase, ScienceDirect and Cochrane Library from January 1990 to October 2021. Studies investigating the association between margin width, margin status and LR rates were considered for inclusion. Study quality was evaluated using the Newcastle-Ottawa Scale (NOS). Meta-analysis was performed using RevMan5.3 software, and statistical heterogeneity was assessed using the Chi-square test and quantified using the I2 statistic. Visual inspection of funnel plots was used to judge publication bias. Results: A total of 34 articles were included in this article, all of which with NOS scores above 5. Regardless of the PT grade, positive margin significantly increased the risk of LR [odds ratio (OR) 3.64, 95% confidence interval (CI): 2.60-5.12]. No significant difference was found in the risk of LR between the margins <1 and ≥1 cm (OR 1.39, 95% CI: 0.67-2.92). For benign and borderline PTs, there were no significant differences of the LR risk between breast-conserving surgery (BCS) and mastectomy (benign OR 0.68, 95% CI: 0.12-3.78; borderline OR 1.14, 95% CI: 0.29-4.51). While the LR risk was significantly increased by BCS for malignant PT (OR 2.77, 95% CI: 1.33-5.74). Discussion: Different surgical management strategies should be considered for different PT grades. BCS was a feasible option and margins <1 cm was not significantly associated with LR risk for all grade of PT. After BCS, benign PT with positive margin could adopt the "wait and watch" strategy with regular follow-up, while borderline and malignant PTs were expected to underwent re-excision to ensure negative margins. More studies are still needed to clarify and update the existing conclusions and improve the prognosis of PT patients.
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Background: The incidence of bilateral breast cancer (BBC) is low, accounting for 5% of patients with breast cancer. This study aimed to investigate the clinicopathological features and prognosis of synchronous bilateral breast cancer (SBBC) and metachronous bilateral breast cancer (MBBC) in the Chinese population. Methods: Patients with BBC, including SBBC and MBBC, were selected from 6,162 breast cancer patients who underwent surgery at the Chinese People's Liberation Army (PLA) General Hospital between January 2007 and December 2019. Furthermore, patients with unilateral breast cancer (UBC) who underwent surgery at the same time were randomly selected at a ratio of 1:2 as the control group. Clinicopathological features and prognosis were compared between the groups. Results: In all, 123 (2.0%) patients with BBC were enrolled in this study, including 98 (1.6%) SBBC and 25 (0.4%) MBBC patients. A total of 280 patients with UBC were selected for the control group. Compared with patients with UBC, patients with SBBC were more likely to be older and have a family history of breast cancer, non-infiltrative carcinoma, lower pathological tumor-node-metastasis (pTNM) stage, and luminal A type breast cancer as their first tumor. Patients with MBBC were more likely to be postmenopausal and have hormone receptor [estrogen receptor (ER)/progesterone receptor (PR)] negativity, a higher pTNM stage, and a triple-negative first tumor. Patients with UBC with ER/PR (-) were more likely to develop contralateral breast cancer (CBC) than those with ER/PR (+). There was no significant difference in overall survival (OS) and disease-free survival (DFS) between patients with SBBC and patients with UBC. Patients with MBBC had worse DFS than those with UBC, but OS was similar for both types of patients. Patients with MBBC <55 years at first diagnosis had significantly shorter DFS compared to those with SBBC and UBC. A multivariate Cox proportional hazards model revealed that age ≥55 years and ER/PR negativity of the first tumor were independent risk factors for OS. Independent risk factors for DFS included MBBC, age <55 years, family history of other malignant tumors, ER/PR (-), lymphovascular invasion, and N stage ≥2 of the first tumor. Conclusions: The OS and DFS of patients with SBBC and UBC were similar. The MBBC patients, especially those <55 years old at first diagnosis, had shorter DFS than patients with UBC.
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Background: Regardless of histological grade, phyllodes tumors (PTs) exhibit the potential of local recurrence. The National Comprehensive Cancer Network (NCCN) recommends wide local excision (WLE) with a 1 cm margin or more for borderline/malignant PTs but excisional biopsy for benign PTs. However, the treatment of benign PTs remains controversial and the clinicopathologic risk factors for the local recurrence is still unclear. Methods: We retrospectively analyzed 238 patients with PTs who underwent surgery at the Chinese PLA General Hospital from January 1, 2006 and April 30, 2020. We stratified our analysis according to histologic grade and explored the clinicopathologic factors to influence local recurrence (LR), including age, histologic grade, history of fibroadenoma, type of surgery [vacuum-assisted biopsy system (VABS), local excision (LE), wide local excision (WLE) and mastectomy]. Results: All 238 cases were categorized as benign (171, 71.8%), borderline (38, 16.0%), or malignant (29, 12.2%). The median follow-up was 50.2 months. In multivariate analysis, histologic grade (P<0.01) and history of fibroadenoma (P<0.01) were independent prognostic factors for LR. No difference existed in the recurrence rate of BPT treated with different surgical procedures (P=0.397), whereas a higher recurrence rate was found in VABS and LE subgroups than in WLE and mastectomy subgroups for borderline/malignant tumors (P<0.01). Conclusions: No association found between surgical modalities and LR rate for BPT. We suggested a "wait-and-watch" policy for patients with unexpected benign subtypes, instead of unnecessary re-excision. In addition, VABS or LE can be treated for BPT with small mass, whereas WLE or even mastectomy should be conducted for borderline/malignant PTs with large mass.
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The use of aerogels to selectively recover oil from oily wastewater is effective but challenging. In this study, a new carboxylated carbon nanotube/chitosan aerogel (CCNT/CA) with switchable wettability was developed as a smart adsorbent for fast oil absorption and oil recovery. Vinyltrimethoxysilane and thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) was grafted onto the surface of the CCNT/CA skeleton, and the resulting smart aerogel (PNI-Si@CCNT/CA) exhibited temperature responsiveness. PNI-Si@CCNT/CA exhibited an excellent reversible conversion between hydrophilicity and hydrophobicity when the temperature was changed to below or above the lower critical solution temperature (LCST) of PNIPAAm (~32 °C). Most importantly, CCNT significantly increased the oil absorption capacity, improved the mechanical properties, accelerated phonon conduction, enhanced thermal conductivity (80.57 mW m-1 K-1), improved the temperature response rate, shortened the oil desorption time (15 min), and improved the oil/water separation efficiency of PNI-Si@CCNT/CA because a strong interface interaction occurred between CCNT and chitosan. Moreover, PNI-Si@CCNT/CA absorbed oil at 45 °C and released the absorbed oil at 25 °C. It maintained its good adsorption performance after 15 cycles, and this was ascribed to its excellent mechanical properties and stable structure.
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Electron-positron pair annihilation into a single photon is studied when a second free electron is present. Focussing on the relativistic regime, we show that the photon emitted in the three-lepton interaction may exhibit distinct angular distributions and polarization properties. Moreover, the process can dominate over two-photon annihilation in relativistic electron-positron plasmas of few-MeV temperature. An analogy with three-body recombination of electrons with ions is drawn.
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Bleeding complications can cause significant morbidities and mortalities in both civilian and military conditions. The formation of stable blood clots or hemostasis is essential to prevent major blood loss and death from excessive bleeding. However, the body's self-coagulation process cannot accomplish timely hemostasis without the assistance of hemostatic agents under some conditions. In the past two decades, topical hemostatic materials and devices containing platelets, fibrin, and polysaccharides have been gradually developed and introduced to induce faster or more stable blood clot formation, updating or iterating traditional hemostatic materials. Despite the various forms and functions of topical hemostatic materials that have been developed for different clinical conditions, uncontrolled hemorrhage still causes over 30% of trauma deaths across the world. Therefore, it is important to fabricate fast, efficient, safe, and ready-to-use novel hemostatic materials. It is necessary to understand the coagulation process and the hemostatic mechanism of different materials to develop novel topical hemostatic agents, such as tissue adhesives and sealants from various natural and synthetic materials. This review discusses the structural features of topical hemostatic materials related to the stimulation of hemostasis, summarizes the commercially available products and their applications, and reviews the ongoing clinical trials and recent studies concerning the development of different hemostatic materials.