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1.
J Ethnopharmacol ; 283: 114716, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34626781

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Fructus Tribuli (FT) has been commonly used as a traditional medicine for thousands of years. With the diverse uses of FT, more attention has been paid to its hepatorenal toxicity. However, the compounds causing the hepatorenal toxicity of FT remain undetermined. Terrestrosin D (TED), a major spirostanol saponin isolated from FT, may exert hepatorenal toxicity. AIM OF THE STUDY: This study aimed to evaluate the potential hepatorenal toxicity of TED, and preliminarily explore the possible mechanism of TED-induced hepatorenal toxicity. MATERIALS AND METHODS: Cytotoxicity assays, a repeated-dose 28-day in-vivo study, a toxicokinetic study, and a tissue distribution study were used to evaluate the potential hepatorenal toxicity of TED. Furthermore, network pharmacology was applied to preliminarily explore the possible mechanism of TED-induced hepatorenal toxicity. RESULTS: Both the in vitro and in vivo studies showed that the spirostanol saponin TED had potential hepatorenal toxicity. Nonetheless, hepatorenal toxicity induced by oral treatment with TED at a dosage range of 5 - 15 mg/kg daily for 28 consecutive days to Sprague-Dawley (SD) rats was reversible after 14 days of TED withdrawal. The toxicokinetic study demonstrated that the systematic exposure of SD rats to TED had an accumulation phenomenon and a dose-dependent trend after a 28-day repeated-dose oral administration. The tissue distribution study revealed that TED had a targeted distribution in the liver and kidneys accompanied by a phenomenon of accumulation in SD rats. Network pharmacology combined with molecular docking methods was used to screen for the key targets (HSP90AA1, CNR1, and DRD2) and the key pathways of TED-induced hepatorenal toxicity. CONCLUSIONS: The spirostanol saponin TED, a major spirostanol saponin isolated from FT, had potential hepatorenal toxicity.

3.
Epilepsia ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34786694

RESUMO

OBJECTIVE: Vigabatrin (VGB) is the first-line treatment for infantile spasms (IS). Previous studies have shown that VGB exposure may cause vigabatrin-associated brain abnormalities on magnetic resonance imaging (MRI) (VABAM). Based on previous studies, this study aimed to go further to explore the possible risk factors and the incidence of VABAM. In addition, diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) were compared to explore whether DWI should be used as a routine examination sequence when MRI is performed in children receiving VGB. METHODS: Children with IS receiving VGB were selected as the study subjects. Whether VABAM occurred or not was categorized as the VABAM group and the non-VABAM group, respectively. Their general clinical data and medication exposure were collected. The possible risk factors of VABAM and different MRI sequences were compared and statistically analyzed. RESULTS: A total of 77 children with IS were enrolled in the study, of which 25 (32.5%) developed VABAM. Twenty-three of the 25 VABAM cases have a peak dosage of VGB between 50 and 150 mg/kg/day. The earliest observation time of VABAM was 30 days. Regression analysis of relevant risk factors showed that the peak dosage of VGB was the risk factor for VABAM. Comparison between different MRI sequences showed that DWI is more sensitive than T2WI to the evaluation of VABAM. SIGNIFICANCE: In our study, the occurrence of VABAM was 32.5%, indicating a higher incidence than in most previous reports. In addition, we once again verified that the peak dosage of VGB was the risk factor of VABAM. Caution should be exercised that our data also suggest that VABAM may occur even using the conventional dosage of VGB (ie, 50-150 mg/kg/day). Therefore, even when using the conventional dosage of VGB, regular MRI examination should be required. Furthermore, DWI sequence should be used as a routine examination sequence when MRI is performed in children with IS who are receiving VGB.

4.
FEBS Lett ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817071

RESUMO

The prevalence of non-alcoholic fatty liver disease (NAFLD) increases with aging. However, the mechanism of aging-related NAFLD remains unclear. Herein, we constructed an aging-related hepatic steatosis model and analyzed the differentially expressed proteins (DEPs) in livers from young and old mice using liquid chromatography-mass spectrometry. 588 aging-related DEPs and novel pathways were identified. Aminoacyl tRNA synthetase complex-interacting multifunctional protein 2 (AIMP2), the most significantly upregulated protein, promoted poly(ADP-ribose) polymerase 1 (PARP1) activation in aging-related hepatic steatosis. Additionally, mice liver-specific O-GlcNAcase knockout promoted AIMP2 and PARP1 expression. O-GlcNAc transferase overexpression and O-GlcNAcase inhibition by genetic or pharmaceutical manipulations increased AIMP2 and PARP1 levels in vitro. Mechanistically, O-GlcNAcylation increased AIMP2 protein stability, leading to its aggregation. Our study reveals O-GlcNAcylated AIMP2 as a novel pathogenic regulator of aging-related hepatic steatosis.

5.
Photonix ; 2(1): 18, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34806024

RESUMO

Protein assays show great importance in medical research and disease diagnoses. Liquid crystals (LCs), as a branch of sensitive materials, offer promising applicability in the field of biosensing. Herein, we developed an ultrasensitive biosensor for the detection of low-concentration protein molecules, employing LC-amplified optofluidic resonators. In this design, the orientation of LCs was disturbed by immobilized protein molecules through the reduction of the vertical anchoring force from the alignment layer. A biosensing platform based on the whispering-gallery mode (WGM) from the LC-amplified optofluidic resonator was developed and explored, in which the spectral wavelength shift was monitored as the sensing parameter. The microbubble structure provided a stable and reliable WGM resonator with a high Q factor for LCs. It is demonstrated that the wall thickness of the microbubble played a key role in enhancing the sensitivity of the LC-amplified WGM microcavity. It is also found that protein molecules coated on the internal surface of microbubble led to their interactions with laser beams and the orientation transition of LCs. Both effects amplified the target information and triggered a sensitive wavelength shift in WGM spectra. A detection limit of 1 fM for bovine serum albumin (BSA) was achieved to demonstrate the high-sensitivity of our sensing platform in protein assays. Compared to the detection using a conventional polarized optical microscope (POM), the sensitivity was improved by seven orders of magnitude. Furthermore, multiple types of proteins and specific biosensing were also investigated to verify the potential of LC-amplified optofluidic resonators in the biomolecular detection. Our studies indicate that LC-amplified optofluidic resonators offer a new solution for the ultrasensitive real-time biosensing and the characterization of biomolecular interactions. Supplementary Information: The online version contains supplementary material available at 10.1186/s43074-021-00041-1.

6.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 37(11): 981-986, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34809737

RESUMO

Objective To investigate how ephrin-A receptor 2 (EphA2) involves in pyroptosis in invasive breast cancer tissues. Methods The protein expression levels of EphA2, NLR family pyrin domain containing 3 (NLRP3), caspase-1, interleukin-1ß (IL-1ß), and intercellular adhesion molecule-1 (ICAM-1) in cancer tissues, paracancerous tissues, and normal breast tissues of breast cancer patients were detected by Western blot; the expression of EPHA2 in cancer tissues and paracancerous tissues of 45 patients with breast cancer was detected by immunofluorescence assay; and the correlation between protein expression of EphA2 and NLRP3, caspase-1, and IL-1ß in patients' cancer tissues was analyzed by Pearson correlation coefficient. Results The protein expression levels of NLRP3, caspase-1, IL-1ß, and ICAM-1 were significantly decreased and the protein expression of EphA2 was significantly increased in cancer tissues compared with those in normal breast tissues and paracancerous tissues. EphA2 level was negatively correlated with the levels of NLRP3, caspase-1 and IL-1ß. Conclusion EphA2 is overexpressed in breast cancer tissues and negatively correlated with pyroptosis.

7.
ACS Nano ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34751559

RESUMO

GSH-mediated liver biotransformation is a crucial physiological process demanding efficient research tools. Here, we report a type of amorphous FexMnyO nanoparticles (AFMO-ZDS NPs) as redox-activated probes for in vivo visualization of the dynamics of GSH-mediated biotransformation in liver with T1-weighted magnetic resonance imaging (MRI). This imaging technique reveals the periodic variations in GSH concentration during the degradation of AFMO-ZDS NPs due to the limited transportation capacity of GSH carriers in the course of GSH efflux from hepatocytes to perisinusoidal space, providing direct imaging evidence for this important carrier-mediated process during GSH-mediated biotransformation. Therefore, this technique offers an effective method for in-depth investigations of GSH-related biological processes in liver under various conditions as well as a feasible means for the real-time assessment of liver functions, which is highly desirable for early diagnosis of liver diseases and prompt a toxicity evaluation of pharmaceuticals.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34767516

RESUMO

This article addresses the distributed cooperative control design for a class of sampled-data teleoperation systems with multiple slave mobile manipulators grasping an object in the presence of communication bandwidth limitation and time delays. Discrete-time information transmission with time-varying delays is assumed, and the Round-Robin (RR) scheduling protocol is used to regulate the data transmission from the multiple slaves to the master. The control task is to guarantee the task-space position synchronization between the master and the grasped object with the mobile bases in a fixed formation. A fully distributed control strategy including neural-network-based task-space synchronization controllers and neural-network-based null-space formation controllers is proposed, where the radial basis function (RBF) neural networks with adaptive estimation of approximation errors are used to compensate the dynamical uncertainties. The stability and the synchronization/formation features of the single-master-multiple-slaves (SMMS) teleoperation system are analyzed, and the relationship among the control parameters, the upper bound of the time delays, and the maximum allowable sampling interval is established. Experiments are implemented to validate the effectiveness of the proposed control algorithm.

9.
Infect Dis Poverty ; 10(1): 133, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34794512

RESUMO

BACKGROUND: Severe fever with thrombocytopenia (SFTS) caused by SFTS virus (SFTSV) was a tick-borne hemorrhagic fever that posed significant threat to human health in Eastern Asia. The study was designed to measure the seroprevalence of SFTSV antibody in healthy population residing in a high endemic region. METHODS: A cohort study was performed on healthy residents in Shangcheng County in Xinyang City from April to December in 2018, where the highest SFTS incidence in China was reported. Anti-SFTSV IgG was measured by indirect enzyme-linked immunosorbent assay and neutralizing antibody (NAb) was detected by using PRNT50. The logistic regression models were performed to analyze the variables that were associated with seropositive rates. RESULTS: Totally 886 individuals were recruited. The baseline seroprevalence that was tested before the epidemic season was 11.9% (70/587) for IgG and 6.8% (40/587) for NAb, which was increased to 13.4% (47/350) and 7.7% (27/350) during the epidemic season, and further to 15.8% (80/508) and 9.8% (50/508) post epidemic. The IgG antibody-based seropositivity was significantly related to the patients aged ≥ 70 years old [adjusted odds ratio (OR) = 2.440, 95% confidence interval (CI): 1.334-4.461 compared to the group of < 50 years old, P = 0.004], recent contact with cats (adjusted OR = 2.195, 95% CI: 1.261-3.818, P = 0.005), and working in tea garden (adjusted OR = 1.698, 95% CI: 1.002-2.880, P = 0.049) by applying multivariate logistic regression model. The NAb based seropositivity was similarly related to the patients aged ≥ 70 years old (adjusted OR = 2.691, 95% CI: 1.271-5.695 compared to the group of < 50 years old, P = 0.010), and recent contact with cats (OR = 2.648, 95% CI: 1.419-4.941, P = 0.002). For a cohort of individuals continually sampled with 1-year apart, the anti-SFTSV IgG were maintained at a stable level, while the NAb level reduced. CONCLUSIONS: Subclinical infection might not provide adequate immunity to protect reinfection of SFTSV, thus highlighting the ongoing threats of SFTS in endemic regions, which called for an imperative need for vaccine development. Identification of risk factors might help to target high-risk population for public health education and vaccination in the future.

10.
Echocardiography ; 2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34806222

RESUMO

Primary cardiac tumors are extremely rare, among which malignancies comprise about 15-25%. As the most common type of primary cardiac malignancies, angiosarcomas tend to arise in the right heart, especially right atrium. In this case report, we presented a 32-year-old female with primary cardiac angiosarcoma in the right atrial appendage detected by transesophageal echocardiography, as it is difficult to display on conventional transthoracic echocardiography.

11.
Front Oncol ; 11: 762147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760706

RESUMO

Objective: To date, well-designed randomized controlled trials examining the safety, efficacy, and long-term outcomes of single-incision laparoscopic surgery (SILS) for colorectal cancer are scarce. The aim of the current study was to compare short-term outcomes of SILS for colorectal cancer with conventional laparoscopic surgery (CLS). Methods: Between June 28, 2017, and June 29, 2019, a single-center, open-label, non-inferiority, randomized clinical trial was conducted at the Department of General Surgery, Ruijin Hospital (North), Shanghai Jiaotong University School of Medicine in Shanghai, China. In total, 200 patients diagnosed or suspected of colorectal cancer (cT1-4aN0-2M0) were randomly assigned to either the SILS or CLS group in a 1:1 ratio. The primary outcome was early morbidity rate. Secondary outcomes included intraoperative outcomes, pain intensity, postoperative recovery, pathologic outcomes, and long-term outcomes. Results: In total, 193 participants (SILS, 97; CLS, 96) were analyzed in the modified intention-to-treat (MITT) population. Among them, 48 underwent right hemicolectomy (SILS n = 23, 23.7% and MLS n = 25, 26%), 15 underwent left hemicolectomy (SILS n = 6, 6.2% and MLS n = 9, 9.4%), 1 underwent transverse colectomy (MLS n = 1, 1%), 57 underwent sigmoidectomy (SILS n = 32, 33% and MLS n = 25, 26%), and 72 underwent anterior resection (SILS n = 36, 37.1% and MLS n = 36, 37.5%). No significant differences were observed in the baseline characteristics. The intraoperative complication was comparable between the two groups [5 (5.2%) vs. 4 (4.2%); difference, 1%; 95% CI, -5.8% to 7.8%; p > 0.999) and so was postoperative complication rates [10 (10.3%) vs. 14 (14.6%); difference, -4.3%; 95% CI, -13.9% to 5.3%; p = 0.392]. The SILS group showed shorter incision length [median (IQR), 4 (3.5-5) vs. 6.6 (6-7.5), p < 0.001] and lower VAS scores on the first [median (IQR), 4 (3-5) vs. 4 (4-5), p = 0.002] and the second day [median (IQR), 2 (1.5-3) vs. 3 (2-4), p < 0.001] after surgery. No statistically significant difference was found in other measured outcomes. Conclusions: Compared with CLS, SILS performed by experienced surgeons for selected colorectal cancer patients is non-inferior with good short-term safety and has the advantage of reducing postoperative pain. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT03151733.

12.
Analyst ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812800

RESUMO

An infrared laser (808 nm) has been coupled with dielectric barrier discharge (DBD) for optical emission spectrometric determination of S and Cl in organic compounds. The use of a continuous wave IR laser with an output power of 1-2 W allows volatilization of analytes from condensed surfaces. Analytes thermally delivered to the gas phase are excited and atomized by the DBD plasma triggered by an alternating voltage of 10 kV at 25 kHz under atmospheric pressure. Direct analysis of S- and Cl-containing organics in manufactured tablets by measuring the S and Cl emissions resulted in a dynamic range of 0.5%-20% with linearities (R2) above 0.93 and limits of detection (LODs) in the µg g-1 range. The detection precision was examined by measuring inter-day and intra-day reproducibilities, leading to relative standard deviations (RSDs) ranging from 4.6% to 15.0%. The feasibility of LA-DBD-OES was further demonstrated with commercial pharmaceutical tablets of sulfadiazine (SDZ) and chloramphenicol (CAP). There is the potential for probing the tablet uniformity by monitoring the elemental emissions of S and Cl. Quantitative results of the commercial tablets were consistent with the indication amounts and were verified by HPLC measurements. All these results suggest the proposed methodology as a promising tool for online analysis of solids and pharmaceutical tablets with minimal sample treatments and rapid detection response.

15.
Cancer Imaging ; 21(1): 59, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758876

RESUMO

BACKGROUND: Functional MRI (fMRI) parameters analysis has been proven to be a promising tool of predicting therapeutic response to induction chemotherapy (IC) in nasopharyngeal carcinoma (NPC). The study was designed to identify and compare the value of fMRI parameters in predicting early response to IC in patients with NPC. METHODS: This prospective study enrolled fifty-six consecutively NPC patients treated with IC from January 2021 to May 2021. Conventional diffusion weighted imaging (DWI), diffusion kurtosis imaging (DKI), intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) protocols were performed before and after IC. Parameters maps (ADC, MD, MK, Dslow, Dfast, PF, Ktrans, Ve and Kep) of the primary tumor were calculated by the Functool post-processing software. The participants were classified as responding group (RG) and non-responding group (NRG) according to Response Evaluation Criteria in Solid Tumors 1.1. The fMRI parameters were compared before and after IC and between RG with NRG. Logistic regression analysis and ROC were performed to further identify and compare the efficacy of the parameters. RESULTS: After IC, the mean values of ADC(p < 0.001), MD(p < 0.001), Dslow(p = 0.001), PF(p = 0.030) and Ve(p = 0.003) significantly increased, while MK(p < 0.001), Dfast(p = 0.009) and Kep(p = 0.003) values decreased dramatically, while no significant difference was detected in Ktrans(p = 0.130). Compared with NRG, ADC-pre(p < 0.001), MD-pre(p < 0.001) and Dslow-pre(p = 0.002) values in RG were lower, while MK-pre(p = 0.017) values were higher. The areas under the ROC curves for the ADC-pre, MD-pre, MK-pre, Dslow-pre and PRE were 0.885, 0.855, 0.809, 0.742 and 0.912, with the optimal cutoff value of 1210 × 10- 6 mm2/s, 1010 × 10- 6 mm2/s, 832 × 10- 6, 835 × 10- 6 mm2/s and 0.799 respectively. CONCLUSIONS: The pretreatment conventional DWI (ADC), DKI (MD and MK), and IVIM (Dslow) values derived from fMRI showed a promising potential in predicting the response of the primary tumor to IC in NPC patients. TRIAL REGISTRATION: This study was approved by ethics board of the Chinese PLA General Hospital, and registered on January 30, 2021, in Chinese Clinical Trial Registry ( ChiCTR2100042863 ).


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Quimioterapia de Indução , Imageamento por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Adolescente , Adulto , Idoso , Benchmarking , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
16.
Sci Rep ; 11(1): 19518, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593908

RESUMO

Targeted observation is an appealing procedure for improving model predictions. However, studies on oceanic targeted observations have been largely based on modeling efforts, and there is a need for field validating operations. Here, we report the results of a field targeted observation that is designed based on the sensitive areas identified by the Conditional Nonlinear Optimal Perturbation approach to improve the 7th day thermal structure prediction in the Yellow Sea. By introducing the technique of cycle data assimilation and the new concept of time-varying sensitive areas, an observing strategy is designed and validated by a set of Observing System Simulation Experiments. Then, the impact of targeted observations was investigated by a choreographed field campaign in the summer of 2019. The results of the in-field Observing System Experiments show that, compared to conventional local data assimilation, conducting targeted observations in the sensitive areas can yield more benefit at the verification time. Furthermore, dynamic analysis demonstrates that the refinement of vertical thermal structures is mainly caused by the changes in the upstream horizontal temperature advection driven by the Yellow Sea Cold Water Mass circulation. This study highlights the effectiveness of targeted observations on reducing the forecast uncertainty in the ocean.

17.
Langmuir ; 37(40): 11737-11749, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34597055

RESUMO

Capillary forces of a shearing liquid bridge can significantly affect the friction and adhesion of interacting surfaces, but the underlying mechanisms remain unclear. We custom built a surface force apparatus (SFA, ±2 µN) equipped with in situ optical microscopy and performed normal and lateral force measurements on a reciprocating water bridge formed between two flat plates. A modified wedge method was developed to correct the unique force measurement errors caused by the changing bridge geometry and position. The results found (1) strong linear relations among the bridge shear displacement, the cosine difference between the left and right contact angles, and the lateral adhesion force and (2) the normal adhesion force increased monotonically up to 13% as the bridge geometry approached its axisymmetric state. Quasi-static force analyses based on a newly developed decahedral model showed good agreement with the experiments and improved accuracy compared with that of cylindrical or rectangular column models previously proposed in the literature. Although limited in certain aspects, this study may (1) prove helpful to the design and analysis of liquid bridge force experiments on platforms similar to the SFA used in this study and (2) help to bridge the gap between friction and liquid bridge physics in the literature.

18.
ACS Appl Mater Interfaces ; 13(40): 48270-48280, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34592810

RESUMO

A superhydrophobic (SHB) surface with an excellent self-cleaning ability is of great significance in both human survival and industrial fields. However, it is still a challenge to achieve large-area preparation of antiabrasive SHB surfaces with great mechanical robustness for broader applications. Thus, a kind of facile SHB coating with excellent liquid repellency and antiresistance is constructed by spraying a fluorine-free suspension consisting of epoxy resin, hexadecyltrimethoxysilane (HDTMS), and silica nanoparticles on a glass sheet. The SHB coating not only shows high adhesion on various materials but also has high water repellency under various test conditions, including tape peeling after blade scraping, sandpaper abrasion, and immersing in a complex environment. Additionally, the SHB spheres coated with laser-induced microstructure armor could form a continuous gas cavity during the water entry process, which is essential to prolonging the drag reduction ability of SHB coatings in liquid. Finally, the prepared robust SHB coatings have been employed in underwater buoyancy enhancement and reducing fluid resistance, which may open new avenues for underwater drag reduction in the field of marine applications.

19.
Materials (Basel) ; 14(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34639888

RESUMO

In the present work, we investigated the possibility of introducing fine and densely distributed α-Al(MnFe)Si dispersoids into the microstructure of extruded Al-Mg-Si-Mn AA6082 alloys containing 0.5 and 1 wt % Mn through tailoring the processing route as well as their effects on room- and elevated-temperature strength and creep resistance. The results show that the fine dispersoids formed during low-temperature homogenization experienced less coarsening when subsequently extruded at 350 °C than when subjected to a more typical high-temperature extrusion at 500 °C. After aging, a significant strengthening effect was produced by ß″ precipitates in all conditions studied. Fine dispersoids offered complimentary strengthening, further enhancing the room-temperature compressive yield strength by up to 72-77 MPa (≈28%) relative to the alloy with coarse dispersoids. During thermal exposure at 300 °C for 100 h, ß″ precipitates transformed into undesirable ß-Mg2Si, while thermally stable dispersoids provided the predominant elevated-temperature strengthening effect. Compared to the base case with coarse dispersoids, fine and densely distributed dispersoids with the new processing route more than doubled the yield strength at 300 °C. In addition, finer dispersoids obtained by extrusion at 350 °C improved the yield strength at 300 °C by 17% compared to that at 500 °C. The creep resistance at 300 °C was greatly improved by an order of magnitude from the coarse dispersoid condition to one containing fine and densely distributed dispersoids, highlighting the high efficacy of the new processing route in enhancing the elevated-temperature properties of extruded Al-Mg-Si-Mn alloys.

20.
Materials (Basel) ; 14(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34639998

RESUMO

Biological matter evolution provides an idea for the human design and synthesis of new materials. However, biomimetic materials only stay in laboratory-scale models, and their large-scale industrial applications are yet to be realized. Here, inspired by nacre's architecture, we report a continuous, large-scale method to fabricate phosphogypsum composites by reactive extrusion strategy. After curing for seven days, with more than 50 wt% of beta-hemihydrate phosphogypsum (ß-HPG), the compressive strength and softening coefficient were 24.98 MPa and 0.78, increasing by 110.0% and 20.0%, respectively, compared to the pouring method. The results show that the screw extrusion process can improve the mechanical strength and waterproof properties of ß-HPG hydration specimens without any special chemical admixtures and cements.

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