Nanocrystalline magnets (SmCo5)94(Cr3C2)6 were prepared using melt-spinning and their magnetic behaviors were investigated by studying their structures and magnetic properties. The alloys prepared ...using rapid solidification consisted of SmCo5 matrix phase, MgCu2-type SmCo2 secondary phase, and small traces of Sm2Co7 phase. The solidification with higher wheel speed were found to be preferable for the formation of single SmCo2 secondary phase. Relatively high coercive values of 28–36 kOe and high reduced remanence of 0.78–0.79 were observed for the SmCo5/SmCo2 nanocrystalline magnets. The shape of the corresponding magnetization curves revealed that two magnetization processes, nucleation and pinning of domain walls, took place in these magnets. The Henkel plots indicated strong inter-grain exchange coupling effect in these ribbons, consequently resulted in the phenomena of domains interacting with each other and enhancement of the remanence in the ribbons.
We study the higher-order neutral dynamic equation {a(t)(x(t)−p(t)x(τ(t)))Δmα}Δ+f(t,x(δ(t)))=0 for t∈t0,∞)𝕋 and obtain some necessary and sufficient conditions for the existence of nonoscillatory ...bounded solutions for this equation.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
A new theoretical model is proposed to describe the mechanical properties of bimodal nanocrystalline (BNC) materials.In this paper, we have studied the effect of grain size on the constitutive ...behavior and fracture of BNC materials. During the plastic deformation, dislocations emission from crack tips on the constitutive behavior of BNC materials are also analyzed, it is found that the nanocracks make a positive effect on the strain hardening instead of leading catastrophic failure. Numerical calculations have been carried out according to the model, the results show that the model can describe the enhanced strength and ductility of BNC materials successfully.
AIM: To investigate clinical outcomes of chronic hepatitis B(CHB) and liver cirrhosis(LC) patients under whole-course management with lamivudine(LAM). METHODS: This was a retrospective-prospective ...cohort study based on two nonrandom cohorts of Chinese patients(LAM group and history control group). Two hundred thirty-eight patients with LAM treatment for at least 12 mo under whole-course management were included in the LAM group. The management measures included regular follow-up and timely adjustment of the therapeutic regimen according to drug-resistance and relapse. Two hundred thirtyeight patients with CHB or LC without any antiviral treatment and with follow-up over 12 mo were included in the history control group. The LAM and control group patients were 1:1 matched by propensity score method to ensure both patients were similar in general datum,sex,age,E antigen,and diagnosis. The incidence rates of endpoint events LC,hepatocellular carcinoma(HCC),and death were compared between the LAM and control groups.RESULTS: Hepatitis B virus-DNA < 1000 copies per m L rate and rate of alanine transaminase < 1.3 of theupper normal limit in LAM and control groups were 89.1% vs 18.5%(P < 0.05) and 89.8% vs 31.1%(P < 0.05),respectively. Viral breakthrough occurred in 77 patients(32.4%); the one-,three-,and fiveyear cumulative rates were 6.8%,33.1%,and 41.3%,respectively. In total,44.5%(106/238) of patients had once stopped LAM,and 63(59.4%) of them developed virologic relapse; the relapse rate of patients with and without reaching Asian Pacific Association for the Study of the Liver endpoint criteria were 52.4% and 69.8%,respectively. Six CHB patients in the LAM group developed LC compared to 47 patients in the control group; the three-,and five-year cumulative rates of CHB at baseline of LAM were lower than those of the control group: 0.7% vs 12.0% and 1.8% vs 23.8%(P < 0.01),respectively. The incidence of HCC in CHB at baseline of LAM was lower than that of the control group; the three-,and five-year cumulative rates were 0% vs 3.2% and 1.1% vs 3.2%(P = 0.05),respectively. The incidence of HCC in LC at baseline of LAM was lower than that of the control group: 9.8%(5/51) vs 25.0%(12/48),and the three-,and five-year cumulative rates were 4.5% vs 20.7% and 8.1% vs 37.5%(P < 0.01),respectively. The mortality rate in the LAM group was lower than the control group. CONCLUSION: Standardized long-term LAM treatment in combination with comprehensive management can reduce the incidence rates of LC and HCC as well as hepatitis B virus-related deaths.
Cemented tungsten carbide with ultra fine grains was prepared via microwave sintering. IDT phase (W3Co3C) was formed on the surface of the samples during the preparation process. Extra carbon black ...was premixed and the influence of carbon content on mechanical properties was studied. The results show that the maximum value of hardness and transverse rupture strength are HRA 93.2 and 3396 MPa respectively when the carbon black content is 0.45%. The microstructure investigated by SEM show that the WC grains growth mainly occurs during the early stage of microwave sintering by the coalescence of grains.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Ni0.5Zn0.5)Fe2O4 ferrite has been sintered via microwave irradiation. The structural, component and magnetic properties of NiZn ferrite was determined by SEM, X-ray powder diffraction (XRD) and ...automatic hysteresis loop magnetometer. Results showed that the material sintered by microwave energy at 1220°C for 20min had a high purity (Ni0.5Zn0.5)Fe2O4 phase. The sample obtained magnetic properties of intrinsic coercivity 222A/m, saturation magnetization 332mT, initial permeability 0.20mH/m and maximum permeability 0.58mH/m. Compared with conventional sintering method, microwave sintering of NiZn ferrite is more efficient and reducing soaking time.
To look for the best method of repairing nose and adjacent tissue defect after burn and observe the effect.
Twelve patients with post-burn nose and adjacent tissue defect deformities hospitalized ...from January 1999 to December 2008 were repaired with expanded forehead flap, pedicled upper-arm flap, axial post-auricular reversed flow island flap, and nasolabial groove flap. Among them, 4 cases with total nasal defect, 8 cases with partial nasal defect; and 3 cases were accompanied with scars on cheek, 5 cases accompanied with scars on forehead, 5 cases accompanied with upper lip ectropion and subtotal upper lip defect. The skin flap size ranged from 3.0 cm x 1.5 cm to 10.0 cm x 8.0 cm.
Five cases were repaired with expanded forehead flap, 3 cases with pedicled upper-arm flap, 1 case with axial post-auricular reversed flow island flap, and 3 cases with nasolabial groove flap respectively. All the 12 flaps survived. Patients were followed up for 1 to 7 years, and nasal function and appearance were obviously impro
This paper describes the densification response and microstructural homogenization of W-Cu composites sintered by using microwave irradiation. Compared with conventional sintering, microwave ...sintering shows a superior capability in promoting W-Cu densification at higher heating rate. Near theoretical density can be achieved under optimum conditions. Additionally, microwave sintering generates non-aggregated and homogeneous microstructure, while coarsened tungsten grains are presented in the microwave-sintered samples. The present work implies that microwave sintering is a promising and time-saving approach to W-Cu materials manufacture.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
As the technological advances, it is possible to perform wide bandwidth signal processing for high range resolution and target identification in the modern radar systems. In order to prevent the ...deleterious effects of dispersion for wideband signals, a wideband signal can be synthesized by coherently combining the individual narrow band components, meanwhile, clutter mitigation, estimation and discrimination of target's velocity is enabled by performing coherent pulse train in each subband. However, the separate and independent processing using conventional Doppler filter bank in a subband can also introduce deleterious effects of target Doppler dispersion among subbands and cause the distortion on synthesized one-dimensional range profile. In this paper, we first analyze the target Doppler dispersion among subbands and deleterious effects of following recombination, and then propose an effective method to eliminate the deleterious effects of target Doppler dispersion in subbands. The method is easy to be realized and tractable and do not require an increment of computation. Its good performance is verified by simulation results.
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