Graphene, as the fundamental two-dimensional carbon structure with exceptionally high crystal and electronic quality, had attracted increasing interest for its promising potential applications. In ...this article, the few-layer graphene sheets have been achieved by the direct current (DC) arc-discharge under hydrogen atmosphere, using pure graphite rods as the electrodes. The influence of hydrogen pressures (e.g. 0.03MPa, 0.05MPa, 0.07MPa) on the products and their electrochemical properties for hydrogen storage were investigated. It is indicated that the graphene sheets were less than 10 layers and with the sizes in range of 200–500nm. Among all graphene sheet samples, the highest capacity for electrochemical hydrogen storage was 147.8mAh/g. Mechanism for electrochemical hydrogen insertion/desertion of such graphene sheet was discussed with respect to the single-layer graphene and multi-layer graphite.
► We synthesize the graphene sheets in hydrogen atmosphere by arc discharge method. ► We examine the microstructure and electrochemical hydrogen storage of the graphene. ► The graphene electrode exhibits the good cyclic H2 storage capacity. ► The H2 storage is due to large interlayer spacing and defects in the graphene.
The trajectory data generated by various position-aware devices is widely used in various fields of society, but its conventional vector representation and various analysis algorithms based on it ...have high computational complexity. This makes it difficult to meet the application requirements of real-time or near real-time management and analysis of large-scale trajectory data. In view of the above challenges, this paper proposes a trajectory data management and analysis technology framework based on the Spatiotemporal Grid Model (STGM). First, the trajectory data is represented by spatiotemporal grid encoding instead of vector coordinates, and it can achieve dimensionality reduction and integrated management of high-dimensional heterogeneous trajectory data. Second, the trajectory computing and analysis methods based on STGM are introduced, which reduce the computing complexity of algorithms. Furthermore, various types of trajectory mining and applications are realized on the basis of high-performance computing technologies. Finally, a trajectory data management and analysis prototype system based on the STGM is developed, and experimental results verify the reliability and effectiveness of the proposed technology framework.
To evaluate the effect of intestinal carbapenem-resistant Enterobacteriaceae (CRE) active screening combined with enhanced intervention in the prevention and control of nosocomial infection in ...patients admitted to the hematological ward.
Patients who were admitted to the Department of Hematology in a tertiary-care general hospital from March 1, 2017 to December 31, 2019 and underwent chemotherapy or immunosuppressive therapy comprised the intervention group. They were screened for intestinal CRE at least thrice. From December 1, 2016 to February 28, 2017, patients who underwent chemotherapy or immunosuppressive therapy without active intestinal CRE screening in the Department of Hematology formed the control group. Both the patient groups were monitored for CRE infection in real time. The
(2) test was used to compare the changes in the CRE infection rate and mortality in high-risk patients before and after the active screening.
During the intervention period, the CRE colonization rate of patients was 16.46% (
A family of random co-poly(amic acid)s containing 4,4′-oxydianiline (ODA) moiety were synthesised in N,N′-dimethylacetamide. The co-poly(amic acid) solutions were used as spinning dope for dry jet ...wet spinning process into as spun poly(amic acid) (PAA) fibres. The polyimide (PI) fibres were obtained from PAA fibres after being imidised and drawn in furnace. The processability and mechanical properties of the fibres were notably improved by incorporating ODA into 3,3′,4,4′-biphenyltetracarboxylic dianhydride/p-phenylenediamine (BPDA/PPD) backbone. The best strength and modulus of BPDA/PPD/ODA PI fibre (diamine mole ratio of PPD/ODA = 85∶15) attained 2·25 and 96·5 GPa respectively, which were approximately three times the tenacity of the BPDA/PPD PI fibre. The SEM image showed that the cross-section of each stage fibres was round and void free. In addition, 'skin-core' and microfibrillar structure were not observed. The thermal properties of PI fibres were also investigated. The results showed that the PI fibres have excellent thermal stability; moreover, the dimensional stability and structural homogeneity of the fibres were significantly improved by heat drawn stage. T
g
was found to be ∼290°C by thermomechanical and dynamic mechanical analyses. The X-ray (wide angle X-ray diffraction and small angle X-ray scattering) experiments indicated that the ordering degree of longitudinal and lateral stacks, as well as the molecular orientation of PI fibre, was improved in the preparation process of fibres. Furthermore, the mechanical properties of fibres are profoundly affected by the heat drawn conditions.
To explore Fertility and disease outcomes in patients with chronic myeloid leukemia (CML) .
Clinical and fertility outcomes of male (from Jul. 1998 to Feb. 2018) and female CML (from Sep. 2009 to ...Feb. 2018) patients were retrospectively analyzed at Peking University People's Hospital.
A total of 49 male CML patients and their spouses were enrolled. Before their spouses conceived, 34 patients were receiving tyrosine kinase inhibitor (TKI) imatinib, 9 with nilotinib, and 6 with dasatinib. At the time of conception, the median age of these male patients was 32 years (range, 25-48 years) , and the median TKI treatment duration was 36 months (range, 0.2-198 months) . One male patient having achieved complete hematologic response yet discontinuing TKI for a year developed a disease progression to blast crisis. The other 48 patients sustained stable disease. The total conception times were 61 and finally 55 infants were born including one with premature birth, two with low birth weight, and one with hypospadias rece
Endoplasmic reticulum stress(ERS)was used as the research emphasis to further investigate the mechanisms of apoptosis of FLT3-ITD-mutated leukemia cells and decreased expression of FLT3-ITD mutated ...protein induced by all-trans retinoic acid(ATRA).
FLT3-ITD-mutated leukemia cell lines(MV4-11 and MOLM13)were treated with ATRA. Flow cytometry was conducted to assess cell apoptosis. Real-time fluorescent quantitative PCR(RT-qPCR)and Western blot were used to detect the expression of ERS-related and autophagy-related genes and protein, respectively.
A low-dose ATRA further increased FLT3-ITD cells and ERS levels. ATRA acted on the ERS-related PERK/eif2ɑ signaling pathway and continued to increase the ERS of FLT3-ITD cells, resulting in an upregulation of apoptotic gene CHOP expression. After the treatment with ATRA, FLT3-ITD protein in FLT3-ITD cells was decreased. Of the two main ERS-related protein degradation pathways, ER-associated degradation(ERAD)and ER-activated autophagy(ERAA), the expression of ERAD-relat
The aging hardening behaviors of Al-0.12Sc and Al-0.12Sc-0.2Zr (wt.%) alloys with the addition of Si range from 0.05 wt% to 0.3 wt% were investigated by microhardness and transmission electron ...microscopy. The results indicate that content of ∼0.15% Si is optimal and Sc–Si clusters forming at the early ageing stage hinder the evolution process of Al3Sc. Upon aging isochronally, Al-Sc-(Zr)–Si alloy shows two stages hardening. The first strengthen stage occurs because of the formation of Sc–Si clusters, and peak hardness of the second stage owes to (Al,Si)3Sc evolving from the clusters. During aging isothermally at 275 °C, Al-Sc-Si and Al-Sc-Zr-Si show similar hardening characteristics. But ageing at 225 °C, the Sc–Si clusters are relatively stable, the second stage increase in the Al-Sc-(0.15, 0.3%)Si alloys have no appearance. Clustering behavior of Sc and Si does not be changed by the addition of Zr. The Al-Sc-Zr-Si alloy exhibits better thermal stability. Because partition of Zr to the preceding formed (Al,Si)3Sc reduces the coarsening rate of the precipitates.
•The effect of Si–Sc clusters is studied in detail in Al-Sc-(Zr)-(Si) alloys.•Content of ∼0.15% Si is optimal for formation sufficient Sc–Si clusters.•The clusters of Sc–Si retard the evolution process of (Al,Si)3Sc.•Al-Sc-(Zr)-(Si) alloys show two-stage hardening affected by Sc–Si clusters.•Clustering behavior of Sc and Si does not be changed by the addition of Zr.
Phase noise in a radar interferogram is directly related to interferometric coherence and the look number of the interferogram. Therefore an optimal radar interferogram filter should incorporate ...information on both interferometric coherence and look number. We present a modification to the commonly used Goldstein filter by suggesting an improved determination of the filtering parameter. Experimental results with both simulated and real data sets show that the new filter offers much better results when used to filter radar interferograms.
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