Gold nanoparticles (AuNPs) decorated CNTs are promising materials for photocatalytics and biosensors. However, the synthesis of AuNPs chemically linked to the walls of MWCNTs is challenging and toxic ...products such as thionylchloride (SOCl
) or 1-ethyl-3(dimethyl-amino) propyl carbodiimide hydrochloride (EDAC) need to be used. This work reports a new approach to prepare gold nanoparticles decorated multiwalled carbon nanotubes (MWCNTs) by using cysteaminium chloride via the formation of a Zwitterionic acide-base bond. The grafting process consists of 3 mains steps: oxidation, thiolation and decoration of AuNPs on the surface of MWCNTs. The completion of each step has been verified out by both spectroscopic (Raman, UV-Vis, FT-IR) and Scanning Electron Miscroscopy (SEM). The chemical bonding states of synthesized products have been proven by X-ray photoelectron spectroscopy (XPS).
In this study, the projected drought characteristics over Vietnam for the future periods of the middle (2046–2065) and end of the 21st century (2080–2099) were investigated under the Representative ...Concentration Pathway (RCP) scenarios RCP4.5 and RCP8.5. The drought characteristics (duration, severity, intensity, inter‐arrival time, and geographic extent) were estimated based on the Palmer Drought Severity Index (PDSI). The PDSI was calculated using temperature and precipitation data from six regional climate downscaling experiments and their ensemble conducted by the Coordinated Regional Climate Downscaling Experiment‐Southeast Asia (CORDEX‐SEA) project. Projected changes of drought characteristics in the future periods were determined with respect to those in the baseline period 1986–2005. Results show biases in the regional climate model (RCM) outputs, namely an underestimation of temperature and an overestimation of precipitation, which also affect the representation of drought characteristics by overestimating the PDSI. In terms of projections, substantial increases of drought duration, severity and intensity, and decreases in the inter‐arrival time are found over the Red River Delta, northern parts of the North Central sub‐region, parts of the Central Highlands and over southern Vietnam. The droughts are projected to be more widespread under scenario RCP8.5 than RCP4.5, especially in southern Vietnam. With the increasing likelihood of droughts in Vietnam as a result of climate change, sustainable water resources management should be taken into account for agriculture, natural ecosystems and social development.
Changes of ensemble drought characteristics in the mid‐future (MF) and far‐future (FF) periods under the RCP4.5 and RCP8.5 scenarios. Left to right are the mean (1) and maximum (2) of drought duration (a, in month), drought severity (b, in %), drought intensity (c, in %), and drought inter‐arrival time (d, in month)
The main aim of this article is to establish an analytical approach on the torsional postbuckling for functionally graded graphene‐reinforced composite (FG‐GRC) laminated circular cylindrical shells ...stiffened by FG‐GRC laminated stiffener system in thermal environment and subjected to torsion loads. The polymer matrixes of shell skin and stiffeners are reinforced by graphene with two graphene reinforcement directions, namely, zigzag and armchair directions. The anisotropic smeared stiffener technique for FG‐GRC stiffener system is used, and the governing equations are established based on the Donnell shell theory with von Kármán–Donnell‐type geometrical nonlinearity and the Airy's stress function. A three‐state solution of deflection is chosen and Galerkin's method is applied, the explicit forms of critical buckling torsion and expression of load‐deflection postbuckling curves relation are obtained. The effects of graphene‐reinforced composite laminated stiffeners, uniformly distributed temperature, the volume fraction of graphene of stiffened shell on the nonlinear torsional buckling behavior are numerically investigated.
This paper presents an analytical approach on the nonlinear vibration of nanocomposite multilayer organic solar cell (NMOSC) subjected to the combination of wind load and uniform temperature change. ...The NMOSC comprises of five layers, which are made of Al, P3HT:PCBM, PEDOT:PSS, Graphene and Glass. Compared to common models of the NMOSC, ITO is replaced by graphene to control the output colors of NMOSC. The nonlinear motion equations and the compatibility equation are deriving by taking into account the effect of viscous damping, von Karman nonlinearity terms, elastic foundations and initial imperfection. The formula of the wind load is improved for consideration in the general case that the direction of the wind load is not just perpendicular to the structure. Four edges of the NMOSC are assumed to be simply supported and immovable in the transverse plane. The Galerkin and Runge – Kutta methods are applied to obtain the dynamic response and the natural frequency of the NMOSC. Four optimization algorithms (Bees Algorithm, Basic differential evolution algorithm, enhanced colliding bodies optimization algorithm, social group optimization algorithm) are used to determine the maximum value of natural frequency of the NMOCS, which depends on nine variables including the geometrical parameters, elastic foundations stiffness and temperature increment. In the numerical results, the effects of elastic foundations, initial imperfection, viscous damping ratio, temperature increment, wind load and the length to width ratio on the dynamic response and natural frequency are considered in details. The maximum values of the natural frequency of the NMOSC with four algorithms are obtained and compared. The results show that the optimal value obtained by four algorithms is close to each other. However, the calculation time with enhanced colliding bodies optimization algorithm is the fastest and with Bees Algorithm is the longest of all.
•The nonlinear vibration of nanocomposite multilayer organic solar cell is studied.•ITO layer is replaced by Graphene layer for reducing the cost and increasing the efficiency.•The nonlinear motion equations and the compatibility equation are derived based on classical plate theory.•The direction of the wind load is assumed to be not just perpendicular to the structure.•Four optimization algorithms are used to determine the maximum value of natural frequency of the solar cell.
The buckling and postbuckling behavior of thin toroidal shell segments composed of auxetic core and graphene-reinforced face sheets under radial loads is reported in the present research combining ...exiting analytical solutions with the new material designs. Three types of graphene distribution of laminated face sheets and the lattice auxetic core are considered for convex, concave toroidal shell segments and cylindrical shells. The honeycomb lattice auxetic core can be modeled applying a homogenization technique. The Stein and McElman approximation can be used for longitudinally shallow shells to establish the nonlinear equilibrium equations in the framework of the Donnell shell theory with geometrically nonlinearities taking into account the two-parameter foundation model. The expressions of the radial load-maximal deflection postbuckling curves are achieved using the Galerkin method. The numerical investigations indicate the remarkably positive effects of honeycomb auxetic core and graphene-reinforced face sheets on nonlinear buckling responses of shells.
Nonlinear buckling and postbuckling of longitudinally compressed carbon nanotube‐reinforced (CNTR) cylindrical shells stiffened by longitudinal or circumferential CNTR stiffeners in thermal ...environments surrounded by elastic medium are presented in the present study. Five linear distributions of CNT are considered for the shell‐stiffener structure system and they are modeled by innovation homogenization technique for CNTR stiffeners. Based on the classical Donnell thin shell theory with von Karman's nonlinearities and the Galerkin procedure, the governing equations can be built to analyze the critical buckling compression and postbuckling compression‐deflection and compression‐shortening behavior. The noticeable effects of volume fraction of CNTs, shell‐foundation interaction stiffnesses, uniformly distributed temperature, and geometric properties of stiffened cylindrical shells on the critical buckling compression and compression‐deflection and compression‐shortening postbuckling behaviors of stiffened CNTR cylindrical shells are obtained and remarked in numerical examinations.
Nonlinear buckling and postbuckling of longitudinally compressed carbon nanotube‐reinforced (CNTR) cylindrical shells stiffened by longitudinal or circumferential CNTR stiffeners in thermal environments surrounded by elastic medium are presented in the present study. Five linear distributions of CNT are considered for the shell‐stiffener structure system and they are modeled by innovation homogenization technique for CNTR stiffeners.…
Objectives
Internal tandem duplications of the Fms-like tyrosine kinase 3 gene (FLT3-ITD) and additional chromosomal abnormalities (ACA) are prognostic factors in patients with acute promyelocytic ...leukemia (APL). This study aimed to determine the effect of the association between FLT3-ITD and ACA in the prognosis of APL.
Methods
This was a retrospective cohort study including 60 patients with APL treated with all-trans retinoic acid (ATRA) and chemotherapy. Five-year overall survival (OS) and progression-free survival (PFS) were analyzed in patient groups according to the presence of FLT3-ITD and ACA.
Results
FLT3-ITD was an independent adverse factor for 5-year PFS, and ACA was an independent adverse factor for 5-year OS. There were significant differences in OS and PFS among the groups: FLT3-ITD-negative without ACA, FLT3-ITD-positive without ACA, FLT3-ITD-negative with ACA, and FLT3-ITD-positive with ACA. The OS times were 52.917, 45.813, 25.375, and 23.417 months, and the PFS times were 48.833, 38.563, 23.250, and 17.333 months, respectively.
Conclusion
FLT3-ITD and ACA are associated with the poorest OS and PFS outcomes in patients with APL treated with chemotherapy plus ATRA.
A new analytical approach to the nonlinear buckling and postbuckling analyses of functionally graded graphene-reinforced composite laminated cylindrical shells stiffened by functionally graded ...graphene-reinforced composite laminated stiffeners under external pressure taking into account the elastic foundation effect in a uniformly distributed thermal environment is presented in this paper. An improved smeared stiffener technique is developed for anisotropic stiffeners, and a special design for ring and stringer functionally graded graphene-reinforced composite laminated stiffeners is presented and successfully applied in this paper. The governing equations for the cylindrical shells are established by using the Donnell shell theory with the geometrical nonlinearity term in the von Kármán sense with the shell-foundation interaction formulated by the Pasternak elastic foundation model. A three-term solution form is chosen for the deflection, the stress function is introduced, and the Galerkin method is used to establish the nonlinear postbuckling relation. The numerical results validate the effects of the stiffeners, volume fraction of graphene, type of graphene distribution of the shell skin and stiffeners with different geometrical parameters, elastic foundation moduli, and uniformly distributed temperature changes on the nonlinear buckling and postbuckling behaviors of stiffened cylindrical shells.
Conical shell panels made of functionally graded materials (FGMs) are rather commonly used by structural engineers. However, due to their complex geometric shape, there are only a few studies on ...conical shell panels made from FGMs. This paper investigates the linear stability analysis of eccentrically stiffened FGM conical shell panels reinforced by mechanical and thermal loads on elastic foundations. The FGM conical shell is in thermal environment and both the panel and the stiffeners are deformed under temperature. The material properties of both the panels and stiffeners are assumed to be temperature-dependent. Classical shell theory and Lekhnitsky’s smeared stiffeners technique are used to set the balance equations and linear stability. Shells are reinforced by stringers and rings. The effects of stiffeners, material, and mechanical and temperature loads on stability of the eccentrically stiffened FGM conical shell panels are analysed and discussed.
Background:Dilated cardiomyopathy (DCM) is an important cause of heart failure and cardiac transplantation. This study determined the prevalence of DCM-associated genes and evaluated the ...genotype-phenotype correlation in Vietnamese patients.Methods and Results:This study analyzed 58 genes from 230 patients. The study cohort consisted of 64.3% men; age at diagnosis 47.9±13.7 years; familial (10.9%) and sporadic DCM (82.2%). The diagnostic yield was 23.5%, 44.0% in familial and 19.6% in sporadic DCM.TTNtruncating variants (TTNtv) were predominant (46.4%), followed byTPM1,DSP,LMNA,MYBPC3,MYH6,MYH7,DES,TNNT2,ACTC1,ACTN2,BAG3,DMD,FKTN,PLN,TBX5,RBM20,TCAP(2–6%). Familial DCM, genotype-positive andTTNtv-positive patients were younger than those with genotype-negative and sporadic DCM. Genotype-positive patients displayed a decreased systolic blood pressure and left ventricular wall thickness compared to genotype-negative patients. Genotype-positive patients, particularly those withTTNtv, had a family history of DCM, higher left atrial volume index and body mass index, and lower right ventricle-fractional area change than genotype-negative patients. Genotype-positive patients reached the combined outcomes more frequently and at a younger age than genotype-negative patients. Major cardiac events occurred more frequently in patients positive with genes other thanTTNtv.Conclusions:The study findings provided an overview of Vietnamese DCM patients’ genetic profile and suggested that management of environmental factors may be beneficial for DCM patients.
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