Single-walled carbon nanotube (SWCNT) nonvolatile thin-film transistors (TFTs) with (Bi,Nd) 4 Ti 3 O 12 (BNT) gate insulators were fabricated. The electrical properties of BNT films and SWCNT/BNT ...TFTs were investigated. The subthreshold swing, the threshold voltage, the channel mobility, and the ON/OFF ratio of SWCNT/BNT TFTs reach to 62.5 mV/decade, 0.45 V, 1.3 × 10 3 cm 2 /Vs, and 1.5 × 10 7 , respectively. Notably, the device shows a memory window of ~4.1 V and a long retention time of ~10 7 s. These mainly attribute to the SWCNTs channel and BNT ferroelectric gate insulator, which induce much larger charge in channel layer. These results suggest that the SWCNT/BNT TFTs are suitable for the next-generation nonvolatile memory devices and integrated circuits.
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► Multilayer hydrogels were prepared by frontal photopolymerization. ► Hydrophilic reactive microgels (HRM) containing C
C double bonds as crosslinkers. ► The multilayer hydrogels ...showed high mechanical strength along parallel direction. ► The multilayer hydrogels were very weak along perpendicular direction.
Multilayer hydrogels were prepared by frontal photopolymerization of acrylamide and 2-acrylamido-2-methylpropane sulfonic acid using hydrophilic reactive microgels (HRM) as crosslinkers instead of conventional crosslinkers. The hydrophilic microgels (HM) were prepared by inverse emulsion photopolymerization and then were chemical modified by
N-methylolacrylamide (NMA) to obtain HRM with C
C double bonds. The HM and HRM was characterized by dynamic light scattering measurements, SEM, TEM and FTIR, respectively. It was found that the resulting multilayer hydrogels showed high fracture strength and high tensile elongation along parallel direction. However their fracture strength and tensile elongation along perpendicular direction was very weak. The swollen multilayer hydrogels were about 1.0–2.0
mm in thickness, the maximal equilibrium swelling degree was only 30.45. The multilayer hydrogels were characterized by DSC, TEM and XRD, respectively. The swelling property and mechanical strength of some typical multilayer hydrogels were studied.
Single crystalline SnS nanowires with an average diameter of 30 nm and lengths of up to hundreds of micrometers were synthesized by using cationic surfactant cetyltrimethylammonium bromide (CTAB), ...together with SnCl
2, oxalic acid (H
2C
2O
4), and sodium sulfide (Na
2S). The crystallity, purity, morphology, and structure features of the-prepared SnS nanowires were investigated by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Raman spectrum.
Previous studies have indicated two main domestic pig dispersal routes in East Asia: one is from the Mekong region, through the upstream region of the Yangtze River (URYZ) to the middle and upstream ...regions of the Yellow River, the other is from the middle and downstream regions of the Yangtze River to the downstream region of the Yellow River, and then to northeast China. The URYZ was regarded as a passageway of the former dispersal route; however, this assumption remains to be further investigated. We therefore analyzed the hypervariable segements of mitochondrial DNA from 513 individual pigs mainly from Sichuan and the Tibet highlands and 1,394 publicly available sequences from domestic pigs and wild boars across Asia. From the phylogenetic tree, most of the samples fell into a mixed group that was difficult to distinguish by breed or geography. The total network analysis showed that the URYZ pigs possessed a dominant position in haplogroup A and domestic pigs shared the same core haplotype with the local wild boars, suggesting that pigs in group A were most likely derived from the URYZ pool. In addition, a region-wise network analysis determined that URYZ contains 42 haplotypes of which 22 are unique indicating the high diversity in this region. In conclusion, our findings confirmed that pigs from the URYZ were domesticated in situ.
As bridge design tends towards longer spans, reducing the structural dead load has become a key challenge. The corrugated steel web (CSW)–prestressed concrete composite box girder is an innovative ...steel–concrete composite structure that effectively reduces the bridge substructure's dead load by reducing the weight of the main girder. However, during CSW welding, thermal deformation due to localised high temperatures is limited by the stiffness of the weldment, and residual welding stresses are generated in the weldment. These stresses can adversely affect the serviceability and construction accuracy of composite bridges. Therefore, in this study, the welding process used for fabricating CSW combined box girders was theoretically analysed and experimentally investigated. First, the generation and distribution of welding residual stresses were analysed, and a calculation method for the residual stresses was derived. Subsequently, a CSW box girder specimen was subject to the welding process, during which temperature and strain tests were performed; the analysis of the measured data revealed changes in temperature and strain during welding. Further, a finite element model for CSW welding was established, and the accuracy of the model was verified by comparison with the measured data. Finally, based on the derived residual stress calculation formula and verified finite element model, a nonlinear buckling analysis of the corrugated web was performed, and the failure mode and load–displacement curve of the corrugated web were derived. The results indicated that weld residual stresses more accurately predicted the results than initial structural defects used in traditional specification methods.
•Welding process of corrugated steel web theoretically and experimentally investigated.•Welding residual stress calculation method proposed.•Method more realistic than existing methods for modelling initial defects.•Effects of welding residual stress on buckling performance of a web plate revealed.•Method provides a scientific basis for engineering design and construction.
Nephrocutaneous fistula (NCF) is a rare and severe complication of renal disease and surgical procedures. Treatments for NCF are based on the renal function, and can include nephrectomy, ...heminephrectomy, nephroureterectomy, endourological maneuvers or antibiotic therapy alone. Here we report a case of a chronic NCF which occurred 5 years after partial nephrectomy. In this report, we describe a new surgical approach for the management of a patient with postoperative NCF. In the present case, in addition to removing the fistulous tract, we also performed an omental flap grafting to tightly cover the kidney. In addition to limiting and controlling the local inflammation, the omental flap prevents contact between the kidney and the flank muscle on its posterior rim. No recurrence or complications occurred throughout 10 months of follow-up. The NCF was successfully treated with completely removal of the sinus tract and omental flap grafting, without nephrectomy. This case adds new aspects to the treatment of NCF.
Firstly, uniform solid MF resin spheres were synthesized by polycondensation using PVA as dispersant and blended with GO to produce MF/GO composite after ultrasonic treatment. MF resin spheres were ...assembled into the GO sheets in the process of mixing. Secondly, HMCS/GN composite was obtained after the pyrolysis of the MF/GO composite under Ar gas protection. PVA and carbonization temperature play an important role in controlling the hollow structure of the MF resin spheres in the second process.
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•The HMCS is coated with GN and homogeneous 3D network structure forms in HMCS/GN composite.•The Csp of HMCS/GN is up to 720Fg−1 at a current density of 0.2Ag−1 and the excellent electrochemical properties are mainly attributed to the synergistic effect of N-doped nature and porous structure of the composite.•PVA plays an important role in controlling the size and hollow structure of MF spheres.
Hollow melamine resin-based carbon spheres (HMCS) clad in graphene (GN) sheets brought an unique three-dimensional (3D) network architecture after the pyrolysis of the melamine-formaldehyde (MF) resin spheres/graphene oxide composite under argon. Polyvinyl alcohol plays an important role in controlling the size and the structure of the MF resin spheres and can induce the formation of hollow nitrogen-containing carbon spheres to produce the HMCS/GN composite after anneal treatment. The diameter of the HMCS can be tuned by changing the carbonization temperature. The HMCS/GN annealed at 600°C exhibits excellent electrochemical performance making it an ideal electrode material for supercapacitors. High specific capacitance of 720Fg−1 at a current density of 0.2Ag−1, 560Fg−1 at 5Ag−1 and 420Fg−1 at 20Ag−1 can be achieved which indicates ideal rate capability. The specific capacitance retains 80.3% after 10000 charge-discharge processes at a current density of 20Ag−1. The excellent electrochemical performance of the HMCS/GN is ascribed to its unique 3D network architecture constructed by the hollow carbon spheres intercalated in GN sheets and the high nitrogen content of the composite.
•Based on density functional theory, potential absorber materials were screened from 540 CuLi-II-IV-VI4 compounds.•22 compounds have band gaps that meet the requirements of ideal band gaps (1.0-1.6 ...eV), and seven of the 22 compounds have effective masses less than 1 m0 in different directions.•CuLiBeGeTe4 is a p-type semiconductor with a suitable band gap, good thermal stability, low effective mass, and high optical absorption coefficient.
An important challenge for Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells is to overcome the open-circuit voltage deficit caused by antisite defects between cations. Herein, we selected Group-II, Group-VI, Group-IV, and Li elements to replace Zn, Sn, S, and half of Cu atoms in kesterite- and stannite-type CZTS, respectively. We used screening methods based on density functional theory to calculate and analyze the relevant properties of 540 CuLi-II-IV-VI4 compounds. The screening results demonstrate that CuLiBeGeTe4 is a p-type semiconductor with a suitable band gap, good thermal stability, low effective mass, and high optical absorption coefficient.
Dietary herbal medicines are widely used for the prevention and treatment of a variety of diseases due to their pharmacological activities in China. Juhua (the flower head of Chrysanthemum morifolium ...Ramat.), the most representative flower-derived one, which is mainly used for the treatment of respiratory and cardiovascular diseases, shows significant activities, such as antimicrobial, anti-inflammatory, and anticancer, and, neuroprotective, as well as effects on the cardiovascular system.
This review aims to provide an overview of the crucial roles of flowers in Chinese dietary herbal medicine, and the pharmaceutical research progress of Juhua (the paradigm of dietary herbal medicine derived from the flower) including its applications in Traditional Chinese medicine and diet, cultivars, phytochemistry, quality control, pharmacology, and toxicity, along with chrysanthemum breeding and biotechnology.
The information associated with Chinese dietary herbal medicine, flower-derived medicine, dietary flower, and pharmaceutical research of Juhua, was collected from government reports, classic books of Traditional Chinese medicine, the thesis of doctors of philosophy and maters, and database including Pubmed, Scifinder, Web of Science, Google Scholar, China National Knowledge Internet; and others.
All flower-originated crude medicines recorded in Chinese pharmacopeia and their applications were summarized for the first time in this paper. The edible history and development of flowers in China, the theory of Chinese dietary herbal medicines, as well as flowers serving as dietary herbal medicines, were discussed. Moreover, applications in Traditional Chinese medicine and diet, cultivars, phytochemistry, quality control, pharmacology, and safety evaluation of Juhua, together with chrysanthemum breeding and biotechnology, were summarized in this paper.
The theory of dietary herbal medicines, which are an important part of the Traditional Chinese medicine system, has a history of thousands of years. Many herbal flowers, serving as dietary herbal medicines, contribute significantly to the prevention and treatment of a variety of diseases for Chinese people. To better benefit human health, more effective supervision practice for dietary herbal medicines is needed. Although various investigations on Juhua have been done, there is a lack of analytical methods for discrimination of cultivar flowers and identification of authenticity. Research on the major compounds with bioactivities, especially those related to its clinical application or healthcare function, as well as their possible mechanize, need be strengthened. More safety evaluation of Juhua should be carried out. The research limitations Juhua is facing exist in all dietary herbal medicine.
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Two-dimensional transition metal dichalcogenides have garnered significant research interest due to their excellent photoelectric properties. However, the low photocurrent to dark current ratio has ...restricted their application in visible light imaging. In this study, we fabricated a high-performance phototransistor using a MoTe 2 and ReS 2 flakes heterojunction to enhance the application potential of phototransistors. The resulting device exhibited a high responsivity of 65.4 A/W, a large current on/off ratio of 43.7, a fast response speed of 480/490 μs, an external quantum efficiency of up to 1.38×10 4 %, specific detectivity reaching up to 6.25×10 12 Jones, a subthreshold swing as low as 125 mV/dec, and carrier mobility up to 319 cm 2 /V·s. Notably, the photodetector based on this heterojunction demonstrates visible light imaging functionality. Our work paves the way for developing high-performance phototransistors.
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