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In order to simultaneously determine the values of total solar irradiance (TSI) and the Earth’s radiation at the top of the atmosphere (TOA) on board the Fengyun-3F satellite, a spaceborne relative radiometer (SRR) was developed. It adopts a dual-channel structure, including a solar radiometer channel (SR) with an unobstructed field of view (FOV) of 1.5° and an Earth radiometer channel (ER) with a wide field of view (WFOV) of 95.3° and a diameter of about 1900 km on the ground. Before the launch, both the SR and ER were calibrated. The SR, installed on the inner frame of the solar tracker of the SIM-II (solar irradiance monitor-II), is used to observe rapid changes in solar radiance with the SIAR (solar irradiance absolute radiometer), an electrical-substitution radiometer, on orbit. The ER is mounted on the U-shaped frame of the solar tracker, directly pointing in the nadir direction. Additionally, a dark space observation mode is used to determine the on-orbit background noise and lunar observation mode for on-orbit calibration. In this article, the instrument design and working principle of the SRR is first introduced, and an analysis of the measurement model of the ER, the WFOV channel of the SRR, is focused on. Finally, ground test results of the SRR are introduced.

This study aims to explore the effects of comprehensive swallowing intervention on obstructive sleep apnea (OSA) and dysphagia in stroke patients.We performed a randomized controlled trial in stroke patients with obstructive sleep apnea (OSA) complicated by dysphagia, divided into treatment group and control group. The treatment group underwent comprehensive swallowing intervention and received swallowing care for 4 weeks, while the control group received only swallowing care. Outcome measurements were obtained at baseline and after the 4-week intervention, evaluated by polysomnography (PSG), videoendoscopic swallowing study (VFSS) synchronized surface electromyography (sEMG), oropharyngeal magnetic resonance imaging (MRI) and swallowing assessment scales.Sixty patients with stroke (30 treatment and 30 control) were eligible to participate in this study. There were no significant differences in any assessment between two groups at baseline. After a 4-week intervention, compared with to control group, there was a significant decrease in the apnea-hypopnea index (AHI) and oxygen desaturation index (ODI), and increased mean and minimal oxygen saturation (SaOThe comprehensive swallowing intervention had therapeutic effects on OSA and dysphagia after stroke, and the mechanism was related to enhancing oropharyngeal muscle strength and changing upper airway structure.

In an attempt to improve the effective utilization of solid waste generated in the steel industry and reduce the production cost of glass ceramics, glass ceramics were prepared from blast furnace slag as the main raw material. The effects of SiO2/CaO molar ratio on the viscosity, structure, and properties of the as-prepared CaO–MgO–Al2O3–SiO2 (CMAS) blast furnace slag glass ceramics were investigated by viscometry, X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and physicochemical property measurements. The results showed that with decreasing SiO2/CaO ratio, the viscosity and degree of polymerization of molten glass significantly decreased, and the main crystalline phase transformed from single diopside to a combination of augite and gehlenite phases, which affected the physicochemical properties of the glass ceramics. The glass ceramic sample with a density of 2.78 g/cm3 exhibited the best comprehensive performance: bending strength of 182.86 MPa, microhardness of 7.34 GPa, acid resistance of 95.21%, and alkali resistance of 98.43%. The various characterization results proved that the prepared glass ceramics could be potentially used for several industrial applications.

A space based relative radiometer has been developed and applied to the PICARD mission. It has successfully measured 37 months solar radiation, terrestrial outgoing radiation, and a comparable interannual variation in Earth Radiation Budget (ERB) is inferred from those measurements [1]. However, since the BOS (Bolometric Oscillation Sensor [2]) relative radiometer is originally designed to measure the solar irradiance with 10 seconds high cadence comparing to the absolute radiometer. The high dynamic range of BOS limits its performance to track the Earth’s outgoing radiation in terms of instantaneous field-of-view (iFOV) and the absolute radiation level. Two relative radiometers (RR) will be developed for JTSIM/FY-3F. One is the solar channel relative radiometer aimed to measure the solar irradiance side by side with the cavity solar irradiance absolute radiometer (SIAR). The second RR is acting as a non-scanner instrument to measure the Earth’s outgoing radiation. Comparing to the design of PICRD-BOS. Each RR has included an aperture, for the solar channel it limits its Unobstructed Field of View (UFOV) to about 1.5 degree and for the Earth channel to about 110 degrees, respectively. We also test the possibility to use the Carbon Nanotube coating on the main detector. In this presentation, the design of the earth channel relative radiometer (ERR) will be introduced, including the aperture design, dynamic range and the active temperature control system. The preliminary laboratory test result of the ERR will be discussed in the end.[1] P. Zhu, M. Wild, M. van Ruymbeke, G. Thuillier, M. Meftah, and Ö. Karatekin. Interannual variation of global net radiation flux as measured from space. J. Geophys. Res. doi:10.1002/2015JD024112, 121:6877–6891, 2016.[2] P. Zhu, M.van Ruymbeke, Ö. Karatekin, J.-P.Noël, G. Thuillier, S. Dewitte, A. Chevalier, C. Conscience, E. Janssen, M. Meftah, and A. Irbah. A high dynamic radiation measurement instrument: the bolometric oscillation sensor (bos). Geosci. Instrum. Method. Data Syst., 4,89-98,:doi:10.5194/gi–4–89–2015, 2015.Acknowledgement: this work is partly supported by the National Natural Science Foundation of China No. 41974207 and CSC Scholarship No.202004910181

In order to support the analysis of potential long-term trends in the Sun’s variability and trace the WRR ground calibration ratio to the measurement on the satellite. We established the total solar irradiance (TSI) calibration model in orbit for the new generation of solar radiation monitor on the FY-3E satellite. First, we measured the non-equivalence of the instrument, and the air to vacuum ratio of the SIAR radiometer is 0.9958-0.9973. Then, we established the temperature correction model for the important parameters, such as the aperture area, the standard voltage and the heating wire resistance. Finally, we calibrated the SIAR with the world radiation reference (WRR) and traced the ground calibration result to the measurement on the satellite. The end-to-end calibration ratio is 0.9991-1.0006, and the uncertainties for three channels are all better than 0.08%.

Permeability is a key parameter influencing fluids flow capacity and the gas production rate of the marine hydrate-bearing sediments. In this study, a series of experiments were carried out to find out the dependence of the gas phase permeability of montmorillonite on different hydrate saturations at effective axial stresses of 1 MPa, 3 MPa. And an experimental study of the decomposition of methane hydrate (MH) by depressurization was carried out. It is found that with the increase of gas hydrate saturation, the gas phase permeability of montmorillonite shows a trend of decreasing first and then increasing, due to the effect of blockage of hydrate particles and the increase of pores in inter-aggregate zones during methane hydrate formation. Furthermore, the gas phase permeability of clay clearly decreases gradually with the increasing decomposition time under different hydrate saturations, due to the formation of the bound water and the swelling of clay. The magnitude of CH4 coefficient of permeability K a and that of transmission D ∗ reache 10−7and 10−8, respectively. K a is also known as hydraulic conductivity in the Darcy law. It is defined as the unit flow rate under the unit hydraulic gradient, indicating the difficulty of the fluid passing through the pore skeleton. And D ∗ is the coefficient of transmission based on a modified form of Fick's law, which is a function of the volume-mass properties of the soil and the gas density. After the complete decomposition of the hydrate, the permeability coefficient K a decreases with the increase of initial hydrate saturation when 4.02% ≤ S h ≤ 15.15%. However, 15.15% ≤ S h ≤ 27.26%, the values of K a increase with the increase of initial hydrate saturation. These experiments helped us understand some important aspects of MH behavior such as saturation of hydrate formation, effective stress, and permeability change during decomposition. This work could be useful to research on the production efficiency of marine gas hydrate reservoir.

The glass and glass ceramics in the CaO–MgO–Al2O3–SiO2 system were successfully synthesized from the stainless steel (SS) slag. The effect of slag content on the viscosity and conductivity of the glass melt, as well as the crystallization behavior and microstructure of the glass ceramics were investigated. The results proved that the viscosity of the molten glass decreases with increasing temperature and SS slag content; however, an inverse relation is observed in case of conductivity. Furthermore, the logarithm of viscosity varies linearly with that of conductivity. Thus, the viscosity and conductivity values can be calculated with respect to each other under melting conditions. The crystallization activation energies range from 335 to 473 kJ/mol, which are significantly higher than the viscous energies and conductance activation energies. Additionally, the obtained glass ceramics comprise augite, gehlenite, and wollastonite. Furthermore, augite grain coarsening and the number of crystals increase with increasing SS slag content.

In an attempt to determine the relationship among the network structure, viscosity, electrical conductivity, surface tension, and density of chromium-containing glass melts, the variation in glass melt thermophysical properties of the CaO–MgO–Al2O3–SiO2 quaternary system were investigated by comprehensive physical property analysis and Raman spectroscopy. The results demonstrated that the network structural units Q n (n = 0, 1, 2, 3) coexisted in the glass melts and their mutual transformation caused changes in the depolymerization degree, leading to a range of viscous activation energies, conductive activation energies, surface tension, and melt densities. Additionally, the logarithm of viscosity varied linearly with the logarithm of electrical conductivity (slope: 0.67–1.54). Meanwhile, the surface tension and melt density decreased with temperature. Consideration of these interrelations is indispensable during the development of chromium-containing slag glass ceramics, particularly for pilot and industrial applications.

Wollastonite-augite glass-ceramics of the CaO–SiO2–Al2O3–MgO system were prepared from stainless steel slag as the main raw material. The effects of SiO2/MgO mass ratio on the crystallization behavior, crystalline phases, structure, and properties of the as-prepared stainless steel slag glass-ceramics were investigated by differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, and physicochemical property measurements. The results showed that with decreasing SiO2/MgO ratio, the crystallization activation energies of the samples decreased from 436.48 kJ/mol to 383.84 kJ/mol, and their crystallization indexes increased from 1.67 to 3.21; in addition, the augite crystals were gradually refined and their content increased. On the other hand, the amount of elongated wollastonite crystals decreased and the crystals gradually dispersed in the augite crystals. Furthermore, among all the prepared glass-ceramics, the one with a density of 3.08 g/cm3 exhibited the best mechanical properties with a bending strength of 176.21 MPa and microhardness of 8.81 GPa.

CaO–MgO–Al2O3–SiO2 glass-ceramics with various Cr2O3 contents are successfully prepared from blast furnace slag as the main raw material using a conventional melting method. The influence of Cr2O3 addition on the viscosity, crystallization kinetics, structure, and properties of the obtained materials are systematically determined by viscometry, differential scanning calorimetry, Fourier-transform infrared spectroscopy, X-ray powder diffraction, thermal-field-emission environmental scanning electron microscopy, and corrosion-resistance property tests. The results showed that the obtained glass-ceramics is composed of dendritic diopside (main crystalline phase) and bulk spinel (second crystalline phase). With increasing amount of Cr2O3, the viscosity of the slag glass melt increases. In addition, the samples exhibit crystallization activation energies in the range 378–454 kJ/mol, with slight fluctuations. Moreover, the crystallization index increases from 0.84 to 2.80. The obtained glass-ceramics exhibit a maximum density, bending strength, and acid and alkali resistances of 2.97 g/cm3, 196.69 MPa, 97.61%, and 98.04% respectively, demonstrating their wide application potential for various industrial applications.

Although AGAMOUS-LIKE6 (AGL6) MADS-box genes are ancient with wide distributions in gymnosperms and angiosperms, their functions remain poorly understood. Here, we show the biological role of the AGL6-like gene, OsMADS6, in specifying floral organ and meristem identities in rice (Oryza sativa L.). OsMADS6 was strongly expressed in the floral meristem at early stages. Subsequently, OsMADS6 transcripts were mainly detectable in paleas, lodicules, carpels and the integument of ovule, as well as in the receptacle. Compared to wild type plants, osmads6 mutants displayed altered palea identity, extra glume-like or mosaic organs, abnormal carpel development and loss of floral meristem determinacy. Strikingly, mutation of a SEPALLATA (SEP)-like gene, OsMADS1 (LHS1), enhanced the defect of osmads6 flowers, and no inner floral organs or glume-like structures were observed in whorls 2 and 3 of osmads1-z osmads6-1 flowers. Furthermore, the osmads1-z osmads6-1 double mutants developed severely indeterminate floral meristems. Our finding, therefore, suggests that the ancient OsMADS6 gene is able to specify "floral state" by determining floral organ and meristem identities in monocot crop rice together with OsMADS1.