[en] Inertial Navigation System (INS) and Global Positioning System (GPS) composite guidance technology are the most advanced all-weather, autonomous guidance technology. The principle is to use a Almanac filter to combine the two and after filtering, give an optimal estimate of a set of state variables (such as position, velocity, attitude angle, gyro drift, accelerometer bias, clock difference, etc.). And periodically feedback back to INS to correct it. The combined system can output all navigation information at a higher rate, superior short-term and long-term accuracy, greatly improve system availability and smoother positioning and output trajectory. The inertial navigation system (Inertial Navigation Oyster, INS) and the satellite-based positioning system represented by GPS have strong complementary advantages. GPS provides high accuracy and stability and continuously monitors the inertia sensor’s error (gyro drift). (paper)

[en] In this paper, a novel hybrid plasmonic nanolaser with a metal ridge and a MgF₂ dielectric layer at ultraviolet band is demonstrated. The electric field distribution, the modal properties, the quality factor and the lasing threshold are investigated by using the finite-element method on the basis of the COMSOL Multiphysics platform. At the 390 nm working wavelength, the structure of the nanolaser can reach good deep-subwavelength mode confinement by optimizing its geometric parameters, while maintaining high quality factor and low propagation loss and low gain threshold. Compared to the previously reported structure with a metal plate, this structure has stronger capacity of field confinement and microcavity bound with the same geometric parameters. The structure shows potential to promote miniaturization and integration of lasers. (authors)

[en] Three-color continuous-variable (CV) entangled beams can be produced by single-pass cascaded sum-frequency processes of third-harmonic generation by quasi-phase-matching technique in only one optical superlattice. Firstly, second-harmonic field is generated by the first double-frequency process of the fundamental field. Then, the third-harmonic field can be generated by the second cascaded sum-frequency process between the second-harmonic and the fundamental fields by quasi-phase-matching technique in the same optical superlattice. By using the quantum stochastic method, we investigated the conversion dynamics of the cascaded sum-frequency processes and the quantum correlation nature among the fundamental, second-harmonic, and third-harmonic fields. The results show that the higher conversion efficiency of third-harmonic generation can be achieved with the larger nonlinear coupling parameter of the second cascaded sum-frequency process. We also show that the fundamental, second-, and third-harmonic beams are CV entangled with each other according to the necessary and sufficient CV entanglement criterion. This scheme of three-color entanglement generation without involving optical cavity is easy to realize in experiment. Moreover, the three-color entangled beams are separated by an octave in frequency which has potential applications in quantum communication and computation networks. (letter)

[en] Objective: To study the influence on the tumor after percutaneous intra-tumor injection of ³²P-GMS in liver cancer as well as its suitable dose. Methods: 24 New Zealand rabbits were used to establish the animal model of VX-2 liver cancer, and divided into A, B and D groups with individually 37, 74, 111 and 148 MBq of ³²P-GMS being injected, respectively; and then pathological changes of tumor were observed by light and electron microscope respectively. Results: The dose of ³²P-GMS was obviously correlated with the radioactivity damage of tumor cells. In the A and B groups, the tumor cells were not observed to disappear completely after injection of ³²P-GMS, but in C group, tumor cells were almost completely disappeared and surrounded by a lot of connective tissue. Although the tumor cells were found to disappear completely in D group, normal liver tissues were also involved. Conclusion: Percutaneous intra-tumor injection of ³²P-GMS with suitable dose that may induce the tumor tissue to be maximally damaged and may also provide some significances to prevent the tumor metastasis. (authors)

[en] Objective: To explore the MRI features of neonatal deep cerebral arterial infarctions. Methods: The medical and MRI datas of 23 neonates with deep cerebral arterial infarctions from January 2011 to December 2018 in Beijing Children's Hospital, Capital Medical University were retrospectively analyzed. Both 11 males and 12 females with ages between 1-28 d were recruited and MRI were performed within 2-20 d after symptom onset. The MRI features including location, morphology, signal characteristics, enhancement features and other accompanied signs were reviewed. Results: A total of 15 cases with arterial infarction and 8 cases with complication of purulent meningitis were identified. The median age at presentation were 2 d and 7 d respectively. The unilateral involvement were demonstrated in all neonates with arterial infarctions. Among them, 11 had deep infarcts and the main branch of the middle cerebral artery was involved in 4 neonates. MRI showed slightly hypo-intensity on T₁WI and slightly hyper-intensity on T₂WI with indistinct boundary and focal punctate hyper-intensity on T₁WI and hypo-intensity on T₂WI. In 8 cases secondary to purulent meningitis, unilateral involvement was found in 5 cases and bilateral involvement in 3 cases. All cases showed hypo-intensity on T₁WI and hyper-intensity on T₂WI with indistinct boundary. Among them, 7 cases were heterogeneous, with small cystic changes which appeared as slightly hyper-intensity on T₁WI and slightly hypo-intensity on T₂WI peripherally, as well as nodular or patchy restricted diffusion. Marked swelling of the lesion was found in 6 cases. Multiple patchy or ring enhancement was revealed in 5 cases. Iso-intensity and restricted diffusion in posterior horn of the lateral ventricle were found in 2 cases. Restricted diffusion in frontotemporal subarachnoid space was found in 5 cases. One case showed subdural effusion. Conclusion: Neonatal deep cerebral arterial infarctions have certain characteristic appearance on MRI. Lesions secondary to purulent meningitis can be bilateral involvement with heterogeneous MRI intensities, and different period of infarction signs could be found concurrently. MRI is beneficial to the differential diagnosis. (authors)

[en] Multi-colour continuous-variable frequency comb entanglement can be directly generated by enhanced Raman scattering in a hexagonally-poled LiTaO₃ optical superlattice. Raman scattering signals are distinctly boosted by a coupled quasi-phase-matching optical parametric amplification process which has been realized in a previous experiment (Xu et al 2005 Phys. Rev . B 72 064307). The conversion dynamics of the coupled optical parametric amplification process is investigated here using quantum stochastic methodology, and the nature of entanglement among the Raman signals is discussed by applying a necessary and sufficient continuous variable criterion. Multi-colour entanglement with the same frequency interval can be obtained directly, with no optical oscillator cavity, in the enhanced Raman scattering process; this has potential application in quantum communication and computation networks. (letter)

[en] We theoretically investigate the generation of five-partite continuous-variable (CV) entanglement through injection-seeded non-degenerate optical parametric amplification cascaded two sum-frequency processes in only one optical superlattice without optical cavities. The idle can be generated by optical parametric amplification of pump and signal. Then, one beam will be generated by the cascaded sum-frequency process of pump and idle, and another beam will be produced by the cascaded sum-frequency process of pump and signal in the same optical superlattice. The phase-mismatching in the cascaded nonlinear processes can be compensated by three reciprocals of the optical superlattice by a quasi-phase-matching technique. The conversion dynamics among the cascaded nonlinear processes is analyzed by using a quantum stochastic method. The five-partite entanglement among pump, signal, idle, and two sum-frequency beams are discussed by applying a sufficient inseparability criteria for the five-partite CV entanglement proposed by Van Loock and Furusawa. This scheme of five-partite entanglement generation with different frequencies has potential applications in quantum communication and computation networks. (letter)

[en] (1 - x)Bi_0.5Na_0.5TiO₃-x(Ba_0.7Ca_0.3)TiO₃ (BNT-xBCT, 0 ≤ x ≤ 0.15) solid solutions have been synthesized by a conventional solid state sintering method for obtaining a morphotropic phase boundary (MPB) with good piezoelectric properties. X-ray diffraction patterns reveal that a MPB of rhombohedral and tetragonal phases is formed at compositions 0.09 ≤ x ≤ 0.12. Addition of BCT into BNT greatly lowered coercive field E_c without degrading remanent polarization P_r. The specimen with x = 0.09 has the good piezoelectric properties: d₃₃ = 125 pC/N and k_p = 0.33. A modified Curie-Weiss law was used to fit the dielectric constant of BNT-xBCT ceramics, and a frequency dispersion was observed during the phase transitions from antiferroelectric to paraelectric in specimens with x exceeding 0.06.

[en] In this work, we investigate collagen protein powder (CPP) extracted from chromium leather scrap waste (CLSW). The composition and molecular weight distribution of CPP were determined by elemental analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. The microstructure and size distribution of CPP were then characterized by scanning electron microscopy (SEM) and nanometer analyzer instrument. Finally, CPP was treated with corn starch (CS), and the swelling behavior of the resulting CPP-CS blend was investigated in order to determine its range of applications. The experimental data showed that CPP contains 13 different amino-acids. CPP also displayed low mineral salt levels and a nitrogen content of 43.84%, indicating its potential use as an organic fertilizer. The molecular weight range of CPP is 6.5 to ~ 26.6 kDa. After the obtained CPP was blended with CS, the CPP-CS blend is endowed with optimal swelling properties and is able to overcome the solubility drawbacks of CPP alone. In addition, when the CPP was used as a natural fertilizer, the germination rate and height of kidney beans obviously increased.

No abstract available