Chlorite,as the most representative gangue mineral associated with specularite,of which the separation of these two minerals is difficult.This paper investigated the depression effect of taurine on specularite/chlorit...Chlorite,as the most representative gangue mineral associated with specularite,of which the separation of these two minerals is difficult.This paper investigated the depression effect of taurine on specularite/chlorite separation via flotation experiments,adsorption tests,contact angle measurements,Zeta potential detection,FT-IR measurements,and XPS analyses.The results of single mineral flotation indicated that chlorite could be depressed selectively by taurine with the recovery of less than 30%,but the floatability of specularite remains high with recovery rate of 81.77%at pH 10.The artificial mixed mineral flotation results confirmed the effectiveness of taurine as a depressant.Surface adsorption,contact angle,and Zeta potential detection revealed taurine primarily adsorbs on the chlorite surface,which hampered the DDA’s subsequent adsorption and results in the chlorite’s poor floatability.The FT-IR spectra and XPS analyses provided further proof that taurine adsorbed on chlorite surface as an electron donor,and part of the electrons transferred from the sulfonic acid group of taurine to metal ions during the adsorption process.In addition,the hydrogen bond between amino-group of taurine and O ions in chlorite surface was also formed in the adsorption process.Finally,optimized adsorption configurations of taurine on chlorite surfaces were proposed.展开更多
BACKGROUND： Because bone marrow mesenchymal stem cells （BMSCs） do not secrete sufficient brain-derived neurotrophic factor （BDNF）, the use of exogenous BDNF could improve microenvironments in injured regions for ...BACKGROUND： Because bone marrow mesenchymal stem cells （BMSCs） do not secrete sufficient brain-derived neurotrophic factor （BDNF）, the use of exogenous BDNF could improve microenvironments in injured regions for BMSCs differentiation. OBJECTIVE： To analyze recovery of the injured spinal cord following BMSCs venous transplantation in combination with consecutive injections of BDNF. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Central Laboratory of First Hospital and Anatomical Laboratory, Fujian Medical University from October 2004 to May 2006. MATERIALS： Human BDNF was purchased from Sigma, USA. METHODS： A total of 44 New Zealand rabbits were randomly assigned to model （n = 8）, BDNF （n = 12）, BMSC （n= 12）, and BMSC＋BDNF （n= 12） groups. Spinal cord （I-2）injury was established with the dropping method. The model group rabbits were injected with 1 mL normal saline via the ear margin vein; the BDNF group was subdurally injected with 100 μg/d human BDNF for 1 week; the BMSC group was injected with 1 mL BMSCs suspension （2 × 10^6/mL） via the ear margin vein; and the BMSC＋BDNF group rabbits were subdurally injected with 100 μg/d BDNF for 1 week, in addition to BMSCs suspension via the ear margin vein. MAIN OUTCOME MEASURES： BMSCs surface markers were detected by flow cytometry. BMSCs differentiation in the injured spinal cord was detected by immunofluorescence histochemistry. Functional and structural recovery, as well as morphological changes, in the injured spinal cord were respectively detected by Tarlov score, horseradish peroxidase retrograde tracing, and hematoxylin ＆ eosin staining methods at 1, 3, and 5 weeks following transplantation. RESULTS： Transplanted BMSCs differentiated into neuronal-like cells in the injured spinal cord at 3 and 5 weeks following transplantation. Neurological function and pathological damage improved following BMSC ＋ BDNF treatment compared with BDNF or BMSC alone （P 〈 0.01 or P 〈 0.05）. CONCLUSION： BMSCs venous transplantation in combination with BDNF subdural injection benefits neuronal-like cell differentiation and significantly improves structural and function of injured spinal cord compared with BMSCs or BDNF alone.展开更多
Silicon nitride(SiNx)is an appealing waveguide material choice for large-scale,high-performance photonic integrated circuits(PICs)due to its low optical loss.However,SiNx PICs require high electric power to realize op...Silicon nitride(SiNx)is an appealing waveguide material choice for large-scale,high-performance photonic integrated circuits(PICs)due to its low optical loss.However,SiNx PICs require high electric power to realize optical reconfiguration via the weak thermo-optic effect,which limits their scalability in terms of device density and chip power dissipation.We report a 6-mode programmable interferometer PIC operating at the wavelength of 1550 nm on a CMOS-compatible low-temperature inductance coupled plasma chemical vapor deposition(ICP-CVD)silicon nitride platform.By employing suspended thermo-optic phase shifters,the PIC achieves 2×improvement in compactness and 10×enhancement in power efficiency compared to conventional devices.Reconfigurable 6-dimensional linear transformations are demonstrated including cyclic transformations and arbitrary unitary matrices.This work demonstrates the feasibility of fabricating power-efficient large-scale reconfigurable PICs on the low-temperature ICP-CVD silicon nitride platform.展开更多
The monolithic integration of soliton microcomb devices with active photonic components and high-frequency electronics is highly desirable for practical applications. Among many materials, silicon nitride(SiN_(x)) wav...The monolithic integration of soliton microcomb devices with active photonic components and high-frequency electronics is highly desirable for practical applications. Among many materials, silicon nitride(SiN_(x)) waveguide layers prepared by low-pressure chemical vapor deposition(LPCVD) have been the main platform for on-chip optical frequency comb generation. However, the high temperatures involved in LPCVD render it incompatible as a back-end process with complementary metal oxide semiconductor(CMOS) or active Ⅲ-Ⅴ compound semiconductor fabrication flows. We report the generation of coherent soliton frequency combs in micro-ring resonators fabricated in deuterated silicon nitride(SiN_(x):D) waveguides with a loss of 0.09 d B/cm. Deposited at 270℃ by an inductance-coupled plasma chemical vapor deposition(ICP-CVD) process, the material preparation and fabrication flow are fully CMOS-compatible. These results enable the integration of silicon-nitride-based optical combs and photonic integrated circuits(PICs) on prefabricated CMOS and/or Ⅲ-Ⅴ substrates, therefore marking a major step forward in Si Nxphotonic technologies.展开更多
In order to investigate the high-temperature evaporation characteristics of multicomponent liquid fuel,three kinds of blended fuel:n-heptane/n-decane/RP-3 aviation kerosene-ethanol were experimentally studied with and...In order to investigate the high-temperature evaporation characteristics of multicomponent liquid fuel,three kinds of blended fuel:n-heptane/n-decane/RP-3 aviation kerosene-ethanol were experimentally studied with and without forced convection.Further,based on zerodiffusion and infinite diffusion concept,this study expanded Thick Exchange Layer evaporation model with Natural Convection effect(NC-TEL)to multicomponent liquid fuels.The experimental results show that the droplet evaporation rate increases significantly with the increase of ambient temperature.Higher temperature leads to more significant relationships between the composition ratio and the evaporation rate.The effect of forced convection is not obviously under the circumstance in this paper.Then,the evaporation models were validated by experimental data.In general,the new NC-TEL model behaves better than the Ranz-Marshall(R-M)model,and the prediction accuracy at high temperature is improved by 8%to 35%.In lower temperature conditions,the prediction of zero-diffusion NC-TEL model is better than the infinite diffusion NC-TEL model.In high-temperature conditions,for n-heptane-ethanol droplet,the predictions of NC-TEL model are accurate,but for n-decane/RP-3 aviation kerosene-ethanol,the predictions are lower than experimental results.This may be caused by the micro-explosion phenomenon and the Marangoni phenomenon.展开更多
基金This work was supported by the National Natural Science of China(51904001)Anhui Provincial Natural Science(2008085QE223)China Postdoctoral Science(2020M673590XB).
文摘Chlorite,as the most representative gangue mineral associated with specularite,of which the separation of these two minerals is difficult.This paper investigated the depression effect of taurine on specularite/chlorite separation via flotation experiments,adsorption tests,contact angle measurements,Zeta potential detection,FT-IR measurements,and XPS analyses.The results of single mineral flotation indicated that chlorite could be depressed selectively by taurine with the recovery of less than 30%,but the floatability of specularite remains high with recovery rate of 81.77%at pH 10.The artificial mixed mineral flotation results confirmed the effectiveness of taurine as a depressant.Surface adsorption,contact angle,and Zeta potential detection revealed taurine primarily adsorbs on the chlorite surface,which hampered the DDA’s subsequent adsorption and results in the chlorite’s poor floatability.The FT-IR spectra and XPS analyses provided further proof that taurine adsorbed on chlorite surface as an electron donor,and part of the electrons transferred from the sulfonic acid group of taurine to metal ions during the adsorption process.In addition,the hydrogen bond between amino-group of taurine and O ions in chlorite surface was also formed in the adsorption process.Finally,optimized adsorption configurations of taurine on chlorite surfaces were proposed.
基金the Major Program of Fujian Provincial Science and Technology Department, No. 2002Y014
文摘BACKGROUND： Because bone marrow mesenchymal stem cells （BMSCs） do not secrete sufficient brain-derived neurotrophic factor （BDNF）, the use of exogenous BDNF could improve microenvironments in injured regions for BMSCs differentiation. OBJECTIVE： To analyze recovery of the injured spinal cord following BMSCs venous transplantation in combination with consecutive injections of BDNF. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Central Laboratory of First Hospital and Anatomical Laboratory, Fujian Medical University from October 2004 to May 2006. MATERIALS： Human BDNF was purchased from Sigma, USA. METHODS： A total of 44 New Zealand rabbits were randomly assigned to model （n = 8）, BDNF （n = 12）, BMSC （n= 12）, and BMSC＋BDNF （n= 12） groups. Spinal cord （I-2）injury was established with the dropping method. The model group rabbits were injected with 1 mL normal saline via the ear margin vein; the BDNF group was subdurally injected with 100 μg/d human BDNF for 1 week; the BMSC group was injected with 1 mL BMSCs suspension （2 × 10^6/mL） via the ear margin vein; and the BMSC＋BDNF group rabbits were subdurally injected with 100 μg/d BDNF for 1 week, in addition to BMSCs suspension via the ear margin vein. MAIN OUTCOME MEASURES： BMSCs surface markers were detected by flow cytometry. BMSCs differentiation in the injured spinal cord was detected by immunofluorescence histochemistry. Functional and structural recovery, as well as morphological changes, in the injured spinal cord were respectively detected by Tarlov score, horseradish peroxidase retrograde tracing, and hematoxylin ＆ eosin staining methods at 1, 3, and 5 weeks following transplantation. RESULTS： Transplanted BMSCs differentiated into neuronal-like cells in the injured spinal cord at 3 and 5 weeks following transplantation. Neurological function and pathological damage improved following BMSC ＋ BDNF treatment compared with BDNF or BMSC alone （P 〈 0.01 or P 〈 0.05）. CONCLUSION： BMSCs venous transplantation in combination with BDNF subdural injection benefits neuronal-like cell differentiation and significantly improves structural and function of injured spinal cord compared with BMSCs or BDNF alone.
基金Innovation Program for Quantum Science and Technology(2021ZD0301400)National Natural Science Foundation of China(61975243,62335019)Science and Technology Program of Guangzhou(202103030001)。
文摘Silicon nitride(SiNx)is an appealing waveguide material choice for large-scale,high-performance photonic integrated circuits(PICs)due to its low optical loss.However,SiNx PICs require high electric power to realize optical reconfiguration via the weak thermo-optic effect,which limits their scalability in terms of device density and chip power dissipation.We report a 6-mode programmable interferometer PIC operating at the wavelength of 1550 nm on a CMOS-compatible low-temperature inductance coupled plasma chemical vapor deposition(ICP-CVD)silicon nitride platform.By employing suspended thermo-optic phase shifters,the PIC achieves 2×improvement in compactness and 10×enhancement in power efficiency compared to conventional devices.Reconfigurable 6-dimensional linear transformations are demonstrated including cyclic transformations and arbitrary unitary matrices.This work demonstrates the feasibility of fabricating power-efficient large-scale reconfigurable PICs on the low-temperature ICP-CVD silicon nitride platform.
基金National Natural Science Foundation of China(61975243)Basic and Applied Basic Research Foundation of Guangdong Province(2019A1515010858,2021B1515020093)+2 种基金Science and Technology Program of Guangzhou(202103030001)Science and Technology Planning Project of Guangdong Province(2018B010114002)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X121).
文摘The monolithic integration of soliton microcomb devices with active photonic components and high-frequency electronics is highly desirable for practical applications. Among many materials, silicon nitride(SiN_(x)) waveguide layers prepared by low-pressure chemical vapor deposition(LPCVD) have been the main platform for on-chip optical frequency comb generation. However, the high temperatures involved in LPCVD render it incompatible as a back-end process with complementary metal oxide semiconductor(CMOS) or active Ⅲ-Ⅴ compound semiconductor fabrication flows. We report the generation of coherent soliton frequency combs in micro-ring resonators fabricated in deuterated silicon nitride(SiN_(x):D) waveguides with a loss of 0.09 d B/cm. Deposited at 270℃ by an inductance-coupled plasma chemical vapor deposition(ICP-CVD) process, the material preparation and fabrication flow are fully CMOS-compatible. These results enable the integration of silicon-nitride-based optical combs and photonic integrated circuits(PICs) on prefabricated CMOS and/or Ⅲ-Ⅴ substrates, therefore marking a major step forward in Si Nxphotonic technologies.
基金co-supported by the National Key R&D Program of China(Nos.2017YFB0202400 and 2017YFB0202402)the National Natural Science Foundaion of China(No.91741125)。
文摘In order to investigate the high-temperature evaporation characteristics of multicomponent liquid fuel,three kinds of blended fuel:n-heptane/n-decane/RP-3 aviation kerosene-ethanol were experimentally studied with and without forced convection.Further,based on zerodiffusion and infinite diffusion concept,this study expanded Thick Exchange Layer evaporation model with Natural Convection effect(NC-TEL)to multicomponent liquid fuels.The experimental results show that the droplet evaporation rate increases significantly with the increase of ambient temperature.Higher temperature leads to more significant relationships between the composition ratio and the evaporation rate.The effect of forced convection is not obviously under the circumstance in this paper.Then,the evaporation models were validated by experimental data.In general,the new NC-TEL model behaves better than the Ranz-Marshall(R-M)model,and the prediction accuracy at high temperature is improved by 8%to 35%.In lower temperature conditions,the prediction of zero-diffusion NC-TEL model is better than the infinite diffusion NC-TEL model.In high-temperature conditions,for n-heptane-ethanol droplet,the predictions of NC-TEL model are accurate,but for n-decane/RP-3 aviation kerosene-ethanol,the predictions are lower than experimental results.This may be caused by the micro-explosion phenomenon and the Marangoni phenomenon.
