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The use of biomass in phenolic resin can not only improve performance and reduce costs but can also reduce pollution and protect the environment. Lignin is a biopolymer with a three-dimensional net...

Background. Uterine fibroids are most common in women aged 30-50 and are the most common benign gynecological tumors. Relevant data suggest that about 25% of patients with uterine fibroids are at childbearing age. Uterine fibroids not only cause the discomfort symptoms, and affect the pregnancy, but also have certain malignant transformation risk, thus needed to be treated positively and promptly. Aim. This study is aimed at exploring the effect of laparoscopic myomectomy and comprehensive rehabilitation nursing on patients with uterine fibroids. Methods. The clinical data of 110 cases of uterine fibroids admitted to our hospital from August 2019 to December 2021 were analyzed retrospectively, and they were divided into two groups according to postoperative rehabilitation strategies. Both groups were treated with laparoscopic myomectomy. The A group was treated with routine rehabilitation strategy, while the B group was treated with comprehensive rehabilitation nursing strategy. The differences in operation-related indicators, stress factors, inflammatory factors, nutritional indicators, knowledge mastery, occurrence of adverse symptoms and pain scores, negative emotion scores, nursing satisfaction, and simplified comfort status scale (GCQ) scores between the two groups under nursing strategies were compared. Results. The postoperative exhaust time ( 13.14 ± 2.03 ) h, bed time ( 9.86 ± 1.94 ) h, postoperative hospital stay ( 4.37 ± 1.31 ) d, and total hospital stay ( 6.78 ± 1.69 ) d in the B group were shorter than those in the A group, and the hospitalization expenses ( 0.74 ± 0.25 ) million were less than those in the A group ( P < 0.05 ). Before operation, stress factors, inflammatory factors, and nutritional indexes were compared between the two groups ( P > 0.05 ). On the 3rd day after operation, tumor necrosis factor-α (TNF-α), cortisol (Cor), norepinephrine (NE), and interleukin-1β (IL-1β) in the two groups showed a significantly upward trend compared with those before operation, and albumin and transferrin were significantly fell compared with those before operation. However, the values of stress factor and inflammatory factor in the B group were significantly lower than those in the A group, and the values after the decrease of nutritional index were significantly higher than those in the A group ( P < 0.05 ). The pain scores at 24 h, 48 h, and 72 h after operation in the B group were significantly lower than those in the A group ( P < 0.05 ). Negative emotions, nursing satisfaction, and GCQ scores were compared between the two groups before intervention ( P > 0.05 ). After the intervention, the scores of Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA) in the two groups were significantly lower than those before the intervention, and the scores of nursing satisfaction and GCQ were higher than those before the intervention. The values of negative emotions in the B group after the decline were significantly lower than those in the A group, while the values of nursing satisfaction and GCQ after the increase were higher than those in the A group ( P < 0.05 ). The excellent and good rate of knowledge acquisition in the B group was 94.55% (52/55), which was significantly higher than 78.18% (43/55) in the A group ( P < 0.05 ). The incidence of adverse symptoms in the B group was 9.09% (5/55), which was lower than 21.82% (12/55) in the A group, while the difference was not statistically significant ( P > 0.05 ). Conclusion. Laparoscopic myomectomy combined with comprehensive rehabilitation nursing can reduce the postoperative stress state of patients with uterine fibroids, improve patient satisfaction, reduce adverse emotions, and promote rehabilitation.

Iron (Fe3+) is one of the most essential elements in the human body; deficiency or overdose of Fe3+ may have adverse effects on human health and immunity. Hence, it is essential to establish a sensitive and selective method for ion detection. In this study, novel green fluorescent N-doped carbon dots (N-CDs) were prepared with caffeic acid as the carbon source via a simple hydrothermal method. The solution of the as-prepared N-CDs exhibits 21.5% quantum yield, good salt stability, excellent water solubility, low cytotoxicity and good photobleaching resistance. The N-CDs can be used as a fluorescent probe for the detection of Fe3+ ions in aqueous solutions and bioimaging in living cells.

With the aim to solve the serious problem of white plastic pollution, we report herein a H2-free low-cost Cu/SiO2 catalyzed process to convert polyethylene terephthalate (PET) into p-xylene (PX) and ethylene glycol (EG) in one pot with methanol as both the solvent and hydrogen source at 210 °C. Kinetic and in-situ Fourier-transform infrared spectroscopy (FTIR) studies demonstrated that the degradation of PET into dimethyl terephthalate (DMT) in methanol involved methanol dehydrogenation and ester hydrodeoxygenation reactions. When preparing the copper silicate precursor using the hydrothermal method with ammonia, NaCl was introduced to interact with the surface hydroxyl groups of SiO2, thereby forming a dense, granular copper silicate with a high Cu+/Cu0 ratio, which improved the methanol dehydrogenation and DMT hydrodeoxygenation activities. This novel H2-free process uses a low-cost Cu-based catalyst, allowing us to produce gasoline and antifreeze components from waste PET plastic in one pot, which provides a feasible solution to the plastic pollution problem in islands.

Reduced dimension is one of the effective strategies to modulate thermoelectric properties. In this work, n-type PbSe/SnSe superlattices with quantum-well (QW) structure are fabricated by pulsed laser deposition. Here, it is demonstrated that the PbSe/SnSe multiple QW (MQW) shows a high power factor of ≈25.7 µW cm-1 K-2 at 300 K, four times larger than that of PbSe single layers. In addition, thermal conductivity falls below 0.32 ± 0.06 W m-1 K-1 due to the phonon scattering at interface when the PbSe well thickness is confined within the scale of phonon mean free path (1.8 nm). Featured with ultrahigh power factor and ultralow thermal conductivity, ZT at room temperature is significantly increased from 0.14 for PbSe single layer to 1.6 for PbSe/SnSe MQW.

A bottom-up geometrical model is established to investigate the mechanical properties of the cable-in-conduit conductors (CICC) superconducting cables for ITER (International Thermonuclear Experimental Reactor). A compact method is formulated to develop the uncompact problems during the construction of the third-stage and fourth-stage strands. Based on the homogenization theory and Costello’s wire rope theory, an analytical model is provided to predict the effective Young’s moduli of the hierarchical superconducting cable. The finite element calculations are performed to analyze the same situation. The numerical results agree well with the results from the analytical model. It is found that the effective Young’s moduli are a function of winding laps for various stages of the strands. This work helps to understand the mechanical properties of the hierarchical superconducting cable and also provides optimal design for higher stage strand.

A series of novel Eu3+ activated aluminate Ba2Y1−xEuxAlO5 (x = 0.02–0.40) red-emitting phosphors were synthesized through a high-temperature solid-state route at 1380 °C. The phosphors were well crystallized in the space group P21/c (No. 14). Their photoluminescence emission (PL) and excitation (PLE) spectra were investigated. The results indicate that the Ba2YAlO5:Eu3+ phosphor can be excited effectively under 394 nm irradiation, which is suitable for UV LED chip. The obtained Ba2YAlO5:Eu3+ phosphor shows four peaks, corresponding to the 5D0–7FJ (J = 0, 1, 2, 3 and 4) transitions of Eu3+ upon 394 nm excitation. The optimal doping concentration of Eu3+ in Ba2YAlO5:xEu3+ was determined at 30 mol%. By temperature dependent emission spectra, the quenching temperature for Ba2YAlO5:0.30Eu3+ was found to be over 500 K. And the CIE chromaticity coordinates of Ba2YAlO5:0.30Eu3+ are very close to the National Television System Committee (NTSC) standard red.

This study concerns a two-dimensional model and the corresponding virtual crack closure technique (VCCT) implemented to solve the general boundary value problems that may explain why interface discontinuity has effects on the fracture behavior in the superconductor-substrate system. The interfacial discontinuity can be classified according to the material properties’ continuity and their derivatives’ continuity at the interface. For nonhomogeneous superconductor and substrate specimens with various material properties, a VCCT method is developed to calculate their fracture behavior. Furthermore, the effects of applied magnetic field amplitude and nonhomogeneous parameters are extensively and parametrically studied in two activation processes (zero-field cooling and field cooling). The integrative and computational study presented here provide a fundamental mechanistic understanding of the fracture mechanism in the superconductor-substrate system and sheds light on the rational design of interfacial continuity. Keywords: Superconductor-substrate system, Interfacial discontinuity, Fracture behavior, Activation processes

Self-assembled nanocomposites with tunable physical properties have potential applications in advanced devices. In this work, self-assembled PbSe:Au films with vertically aligned nanopillars (VAN) were fabricated by pulsed laser deposition. Detailed heterostructures with atomic-resolution have been investigated by cross-sectional scanning tunnelling microscopy. The results show that self-assembled Au nanopillars in a PbSe matrix is realized. Compared with PbSe matrix, PbSe:Au vertical interface can facilitate energy filter effect and lower the in-plane thermal conductivity. The maximum ZT values for n-type self-assembled VAN film is ~2.6 at 523 K, which is ~400% higher than that of pure PbSe film (ZT=0.5). This study suggests that the vertical interface in the unique VAN provide a viable route to manipulate the thermoelectric properties for the thermoelectric materials.

More and more astronomical instruments have been installed in extreme environment such as Antarctica because of good seeing. However it’s not good for electromechanical system of astronomical telescope due to the harsh environment. This paper presents the study of the unanticipated states of direct drive system of extremely large telescope in extreme environment. The unanticipated states which are short of priori knowledge will degrade the reliability of monitor system significantly and put the self-diagnosis system into trouble.

A Latent Variable Mining strategy for unanticipated state diagnosis in a telescope drive system has been proposed in this study. Compared with the existing analysis methods of explicit variables commonly used in fault diagnosis, the latent variable mining method proposed in this paper has the advantage of mining the deep hidden information of the system. First, a strategy for extracting latent variables with Stable Kernels Representation as the detection statistics is established in this paper. Then, principal component regression is used to construct an unanticipated fault diagnose strategy. Finally, an experimental platform for unanticipated load variation of the telescope drive system is established in the article, and the method proposed in this article is used to perform diagnostic tests on it. The test results show that for the unanticipated faults that cannot be correctly identified by the explicit variable analysis, the latent variable analysis method can clearly distinguish them to achieve the purpose of unanticipated fault diagnosis. All of the above show a good performance of the proposed unanticipated diagnosis strategy based on Latent Variable Mining with telescope drive system.

A series of novel Eu3+-doped LiSrBiTeO6 red-emitting phosphors were prepared by the solid-state reaction method for the first time. Its crystal structure and luminescence properties are investigated. X-ray powder diffraction patterns in combination with the Rietveld method reveal its single phase structure. The phosphor can be efficiently excited by 394 nm and 465 nm light and emits bright red luminescence at 616 nm corresponding to the electric dipole transition 5D0–7F2. The optimal doping concentration of LiSrBi1-xTeO6:xEu3+ is about 40 mol%. The thermal stability of the phosphor was tested by measuring their temperature-dependent emission intensities. The warm white light LEDs was fabricated based on the InGaN-chip. The chromaticity coordinates of fabricated w-LED are (0.344, 0.381). All results indicated that LiSrBiTeO6:Eu3+ phosphors have potential application as red phosphors in white light emitting diodes.

Eu2+-doped bromophosphateapatite Sr5(PO4)3Br phosphors were synthesized by the conventional high-temperature solid-state reaction. The crystal structure and luminescence properties of the phosphors, as well as their thermal stability and CIE chromaticity coordinates were systematically investigated. Photoluminescence spectra of Sr5(PO4)3Br:Eu2+ exhibit a single blue emission at 450 nm under the excitation of 345 nm, which is ascribed to the 4f–5d transition of Eu2+. The phosphor shows very good thermal stability. The CIE color coordinates are very close to those of BaMgAl10O17:Eu2+ (BAM). All the properties indicate that the blue-emitting Sr5(PO4)3Br:Eu2+ phosphor has potential application in white LEDs.

A new green-emitting phosphor of Ce3+-doped CaGd4F14 (1–15 mol%) was synthesized by a facile solid-phase reaction. The crystal phase was investigated via X-ray polycrystalline powder diffraction (XRD) and Rietveld refinement. The scanning electron microscopy (SEM), photoluminescence (PL), decay lifetime and quantum efficiency (QE) were applied to characterize the phosphor. The phosphor shows the excitable wavelength in the UV region of (220–320 nm). CaGd4F14:Ce3+ has a green-emission band from 400 to 625 nm with maximum wavelength at 525 nm, which is the typical electronic transitions of 4f-5d of Ce3+-ions. The maximum QE was measured to be 67%. And the phosphor presents good thermal luminescence stability on temperature quenching. The thermal quenching energy is 0.503 eV. This phosphor has a potential application in lighting and display.

Eu2+-doped borate fluoride Ba2GaB4O9Cl was synthesized by the conventional high-temperature solid-state reaction. The crystal structure and luminescence properties of the phosphors, as well as their thermal luminescence quenching capabilities and CIE chromaticity coordinates were systematically investigated. Under the excitation at 340 nm, the phosphor exhibited an asymmetric broad-band blue emission with a peak at 445 nm, which is ascribed to the 4f–5d transition of Eu2+. It was further proved that energy transfer among the nearest neighbor ions is the major mechanism for concentration quenching of Eu2+ in Ba2−xGaB4O9Cl:xEu2+ phosphors. The luminescence quenching temperature is 432 K. The CIE color coordinates are very close to those of BaMgAl10O17:Eu2+ (BAM). All the properties indicated that the blue-emitting Ba2GaB4O9Cl:Eu2+ phosphor has potential application in white LEDs.

A new fluoride phosphor of Eu2+-activated Ba2Zn7F18 has been prepared via two-step solid-phase synthesis. Pure crystalline formation was verified by the X-ray diffraction (XRD) Rietveld refinement. The photoluminescence (PL) spectrum, decay curves (lifetimes), time-resolved emission, and internal quantum efficiency (QE) of Ba2Zn7F18:Eu2+ were characterized. The phosphors show sensitive response to near-UV excitation and emit blueish green luminescence with a maximum quantum efficiency of 70%. The excitation band can well match with the commercial near-UV LED chips (360–400 nm). This is favourable for fabricating white LED lighting devices. The scintillating properties were also confirmed under excitation of X-ray irradiation with a lifetime of 850 ns. Eu2+-activated Ba2Zn7F18 has a high thermal stability with activated energy of 0.63 eV. It could be potential for high-performance lighting and scintillator due to desirable luminescence properties.

A series of novel garnet-type tellurate red-emitting phosphors Li 3 Gd 3(1- x ) Te 2 O 12 : x Eu 3+ ( x = 0.01–0.30) were successfully synthesized by a high-temperature solid-state reaction method. The phase structure, photoluminescence properties and thermal stability of the phosphor were investigated in detail. The phosphor shows dominant emission peak at 613 nm belonging to the 5 D 0 → 7 F 2 electric dipole transition under 396 nm excitation. The luminescence intensity keeps increasing with increasing the content of Eu 3+ to 15 mol%, and the critical transfer distance of Eu 3+ was calculated to be 14 A. The quenching temperature for Li 3 Gd 3 Te 2 O 12 :0.15Eu 3+ was estimated to be above 500 K. This spectral feature reveals high color purity and excellent chromaticity coordinate characteristics. Therefore, Eu 3+ -doped Li 3 Gd 3 Te 2 O 12 phosphors are potential red phosphors for near-UV chip-based white light-emitting diode and display devices.

A series of novel bismuthate tellurate SrBi 2(1- x ) Eu 2 x TeO 7 ( x = 0.02–0.40) red-emitting phosphors were successfully prepared through a high-temperature solid-state reaction at 800 °C. The compounds crystallized in the cubic structure with the space group Pa 3 ¯ . Photoluminescence characteristics indicate that the SrBi 2 TeO 7 :Eu 3+ phosphor can be excited effectively under 465 nm irradiation, which matches well with the output wavelength of blue LED chips. The emission spectrum of SrBi 2 TeO 7 :Eu 3+ phosphor shows four peaks assigned to the 5 D 0 – 7 F J ( J = 0–4) transitions of Eu 3+ upon 394 and 465 nm excitation. The maximum photoluminescence intensity was found at 30 mol% in the SrBi 2 TeO 7 : x Eu 3+ phosphors. The quenching temperature for SrBi 2 TeO 7 :0.30Eu 3+ was revealed at 403 K by temperature dependent emission spectra. The CIE chromaticity coordinates of SrBi 2 TeO 7 :0.30Eu 3+ are very close to the National Television System Committee (NTSC) standard red.

A series of novel garnet-type tellurate orange-red emitting phosphors Li3Gd3(1−x)Te2O12:xSm3+(x = 0.003–0.10) were successfully synthesized by a high-temperature solid-state reaction method. The compounds were crystallized in the cubic structure with the space group of Ia $$\bar 3$$ d. The excitation spectrum indicates that the Li3Gd3Te2O12:Sm3+ phosphor can be excited efficiently under 406 nm irradiation, which matches well with the output wavelength of UV LED chips. The photoluminescence spectrum of Li3Gd3Te2O12:Sm3+ phosphor shows four peaks assigned to the 4G5/2–6HJ (J = 5/2, 7/2, 9/2, and 11/2) transitions of Sm3+. The luminescence intensity keeps increasing with increasing the content of Sm3+ to 2 mol%. The quenching temperature for Li3Gd3Te2O12:0.02Sm3+ was estimated to be above 480 K. Therefore, Sm3+-doped Li3Gd3Te2O12 phosphors are potential orange-red emitting phosphors for near-UV chip-based white light-emitting diode and display devices.

This paper describes a numerical model to examine the magnetostriction of bulk high-temperature superconductor (HTS) under non-uniform magnetic field in conjunction with finite element analysis. Through this model, the magnetostriction of homogeneous and nonhomogeneous HTS can be implemented under non-uniform magnetic field. Further, the effects of critical current density, applied field frequency and amplitude are also considered. The computational study can provide a fundamental mechanistic understanding the effects of non-uniform magnetic field on magnetostriction of HTS.

Superconducting multifilamentary N b 3 S n strand and cables have complex microstructure and macrostructure which are used in the International Thermonuclear Experimental Reactor (ITER) superconducting magnet system. In a generic form, the superconducting strand is made of copper, multifilamentary N b 3 S n and bronze which is a composite. The twisted composite strands form the superconducting cables with typical multi-stage structures. Here we propose a numerical model focusing on the problem of characterizing the effective properties of composite superconducting strand and cables at microscopic and macroscopic scales. The effective elastic constants of the composite superconducting strand can be derived by involving the combination of the representative volume element (RVE) and the Mori-Tanaka method. Subsequently, the proposed method is applied to capture the effects of temperature on the effective elastic constants of the superconducting multi-stage cables. Results show the elastic constants predicted by this model agree well with existing theoretical predictions and available experimental data. This numerical model may be utilized to optimize the mechanical properties of the composite superconducting strand by tuning the constituent fractions and to control the tensile stiffness of superconducting cables by tuning the winding laps of the cables.

Superconducting cable-in-conduct-conductors (CICC) are multi-stage structures with complex geometries. We study the contact behavior and tensile stiffness for a new design of CICC. The geometrical configurations of the new design of CICC is first formulated. Based on the superposition principle, a simple theoretical model is proposed to study the contact behavior of the new design of CICC. A wide range of numerical simulations have been performed by using finite element method. The contact force and tensile stiffness are analyzed by changing the winding laps of C u strand. Further, an extensive parametric study is conducted in which the effect of tensile stiffness on the contact properties are also considered. The results show the trend of the contact properties and tensile stiffnesses in the new design of CICC which can be used to optimize the superconducting CICC. This analytical and computational studies provide a guide for new design of CICC to improve the mechanical properties of CICC by controlling the winding patterns of each strand.

To analyze the fracture problem of the nonhomogeneous high temperature superconductor (HTS) slab under electromagnetic force, we derive the real fundamental solutions based on eigenvalue and eigenvector analyses. The superconductor E-J constitutive law is characterized by the Bean model where the critical current density is independent of the flux density. Fracture analysis is performed by the methods of singular integral equations which are solved numerically by Lobatto–Chybeshev collocation method. Numerical results of the stress intensity factor (SIF) are obtained. Moreover, the crack opening displacement (COD) can be obtained by numerical integration dislocation density functions. The effects of the thickness ratio, HTS material nonhomogeneous parameters, applied magnetic field and critical current density on SIF and COD are discussed. The present work could theoretically provide quantitative predictions of the fracture mechanism of the nonhomogeneous HTS.

The synthesis and transformations of a π-conjugated tellurophene-containing polymer are described. A π-conjugated tellurophene-containing polymer was obtained in 56% yield by the Sonogashira-Hagihara cross-coupling polycondensation of 2,5-di(4-bromophenyl)tellurophene and 1,4-bis(2-ethylhexyloxy)-2,5-diethynylbenzene at 80 °C for 24 h using tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3)/2-dicyclohexylphosphino-2,4,6-triisopropylbiphenyl (XPhos) as a catalyst and triethylamine as a base. The resulting polymer was transformed to a reactive lithiated polymer by the reaction with n-butyllithium (2.4 equiv) at −78 °C to −60 °C for 3 h, which was further converted into a butadiene-containing and a germole-containing π-conjugated polymers by the reactions with hydrochloric acid and dimethylgermanium dichloride at −60 °C to ambient temperature for 12 h in 83% and 85% yields, respectively, by precipitation into MeOH. The obtained germole-containing polymer reveals the absorption onset (λonset) at 492 nm which is longer than those of the tellurophene-containing polymer and butadiene-containing polymer (λonset = 488 nm and 472 nm, respectively), presumably due to the lowering of the LUMO energy level by the σ*-π* orbital interaction. The germole-containing polymer exhibit a blue photoluminescence with an emission maxima (Emax) at 471 nm.

A simple method was developed to prepare fluorescent nitrogen/boron-doped carbon dots (N,B-CDs) in the gram scale. The results showed that the CDs exhibited blue photoluminescence (PL) under 365 nm ultraviolet radiation and excitation-dependent emission. Heteroatoms entered the CDs to enhance the photochemical properties, and their positive properties can be attributed to the presence of guanidino group and functionalized with boronic acid for realizing their utilization in certain applications. These materials could be applied to monitor Fe3+ via static PL quenching, yielding a limit of detection (LOD) of 0.74 μM. Furthermore, the charged and boronic acid groups on the prepared N,B-CDs enabled their use as recognition elements to bind with the bacteria through electrostatic interaction and allowed covalent interactions to form the corresponding boronate ester with E. coli (E. coli) bacterial membrane. This method could satisfy a linear range of 102–107 with LOD of 165 cfu ml−1 for E. coli. This method was applied for the determination of E. coli in tap water and orange juice samples, and satisfactory results were obtained.

Sodium-ion batteries have attracted worldwide attention as potential alternatives for large scale stationary energy storage due to the rich reserves and low cost of sodium resources. However, the practical application of sodium-ion batteries is restricted by unsatisfying capacity and poor rate capability. Herein, a novel mechanism of improving both interfacial and surface charge transfer is proposed by fabricating a graphene oxide/SnO

SnS

This paper presents a fully coupled model to account for the flux pinning induced giant magnetostriction in type-II superconductors under alternating magnetic field The superconductor E-J constitutive law is characterized by power law where the critical current density is assumed to depend exponentially on the flux density. The governing equations of the two-field problem (i.e., the interactions of elastic and magnetic effects) are formulated in a two-dimensional model. The magnetostriction curves and magnetization loops are calculated over a wide range of parameters. The effects of applied magnetic field frequency f and amplitude B0 and critical current density on magnetostriction and magnetization are discussed. Results show that the critical current density of high temperature superconductor (HTS) YBCO has a significant effect on the magnetization and magnetostriction. The pinning-induced magnetostriction which has been observed in experiment can be qualitatively simulated by this model.

Real fundamental solution for fracture problem of transversely isotropic high temperature superconductor (HTS) strip is obtained. The superconductor E–J constitutive law is characterized by the Bean model where the critical current density is independent of the flux density. Fracture analysis is performed by the methods of singular integral equations which are solved numerically by Gauss–Lobatto–Chybeshev (GSL) collocation method. To guarantee a satisfactory accuracy, the convergence behavior of the kernel function is investigated. Numerical results of fracture parameters are obtained and the effects of the geometric characteristics, applied magnetic field and critical current density on the stress intensity factors (SIF) are discussed.

The coupled magneto-mechanical model is established for the dynamic fracture problem for the high temperature superconductor (HTS). The superconductor E-J constitutive law is characterized by power law model where the critical current density is assumed to depend exponentially on the flux density. The cracked superconductor under dynamic loading are employed to investigate dynamic fracture behavior such as the variation of dynamic stress intensity factors (DSIFs) for different applied magnetic field amplitude, the thickness of HTS, and critical current density. To evaluate DSIFs for a type-II superconductor under alternating magnetic field, the flux pinning induced magnetoelasticity model proposed to evaluate DSIFs, and is implemented in conjunction with finite element method. The results show that the applied magnetic field amplitude, thickness of HTS, and critical current density are three important factors affecting the dynamic fracture behavior of the HTS. (C) 2013 Elsevier B.V. All rights reserved.

Based on the analysis of the side peaks in passive radar using digital video broadcasting-terrestrial (DVB-T) signal, two methods for the side peaks interference suppression are presented: the side peaks identification (SPI) method and the side peaks elimination-intersection (SPE-I) method. The SPI method identifies the side peaks by their positions and amplitudes relative to the main peaks. The SPE-I method eliminates the intra-symbol side peaks and the inter-symbol side peaks by preprocessing the reference signal respectively, and obtains the main peaks from the intersection of the peak positions in the two cross-ambiguity function (CAF) diagrams. The SPI method can identify the side peaks without the power loss and may lose the main peaks masked by the side peaks. The SPE-I method can eliminate the side peaks and detect the main peaks masked by the side peaks at the expense of the power loss. Combination of the SPI method and the SPE-I method can overcome their disadvantages. The proposed methods can avoid the false alarms of the side peaks and improve the target detection performance.

In this letter, the shielding or anti-shielding effect is firstly applied to obtain the behavior of two parallel cracks in a two-dimensional type-II superconducting under electromagnetic force. Fracture analysis is performed by the finite element method and the magnetic behavior of superconductor is described by the critical state Bean model. The stress intensity factors at the crack tips can be obtained and discussed for decreasing field after zero-field cooling. The shielding or anti-shielding effect at the crack tips depend on the distance between two parallel cracks and the crack length. The results indicate that the shielding effects of the two parallel cracks increase when the distance between the two parallel cracks decreases. It can be also obtained that the superconductors with shorter cracks has more remarkable shielding effect than those with longer cracks.

Passive radar is one of the current research focuses. The implementation of the Chinese standard digital television terrestrial broadcasting (DTTB) creates a new opportunity for passive radar. DTTB system contains single-carrier and multicarrier application modes. In this paper, ambiguity functions of the DTTB signals in the single-carrier and multicarrier application modes are analyzed. Ambiguity function of the DTTB signal contains one main peak and many side peaks. The relative positions and amplitudes of the side peaks are derived and the reasons for the occurrence of the side peaks are obtained. The side peaks identification (SPI) algorithm is proposed for avoiding the false alarms caused by the side peaks. Experimental results show that the SPI algorithm can indentify all the side peaks without the power loss. This research provides the foundation for designing the DTTB based passive radar.

This Letter presents a theoretical analysis to the fracture behavior of a large single domain YBCO superconductor under thermal stress based on the two-dimensional theory of anisotropic thermoelasticity, the coupled finite element and infinite element numerical method. The thermal stress intensity factors are obtained due to a uniform heat flux by a line crack in a generally half plane superconductor. It is found that the thermal stress intensity factors decrease with the decrease of temperature, and while the longer the crack length is, the larger the stress intensity factors. Additionally, the J-integral at the crack tip is also investigated, a similar behavior to the thermal stress intensity factors is found. These results are benefit for us to understand the fracture mechanism of superconductor both in theory and application.