Up to 9% of the global CO_(2) emissions come from the iron and steel industry. Here, a combined chemical looping process to produce CO, a building block for the chemical industry, from the CO_(2) -rich blast furnace g...Up to 9% of the global CO_(2) emissions come from the iron and steel industry. Here, a combined chemical looping process to produce CO, a building block for the chemical industry, from the CO_(2) -rich blast furnace gas of a steel mill is proposed. This cyclic process can make use of abundant Fe_(3)O_(4) and CaO as solid oxygen and CO_(2) carriers at atmospheric pressure. A proof of concept was obtained in a laboratory-scale fixed bed reactor with synthetic blast furnace gas and Fe_(3)O_(4) /CaO = 0.6 kg/kg. CO production from the proposed process was investigated at both isothermal conditions(1023 K) and upon imposing a temperature program from 1023 to 1148 K. The experimental results were compared using performance indicators such as CO yield, CO space time yield, carbon recovery of the process, fuel utilisation, and solids’ utilisation.The temperature-programmed CO production resulted in a CO yield of 0.056 ± 0.002 mol per mol of synthetic blast furnace gas at an average CO space time yield of 7.6 mmol kgFe^(-1) s^(-1) over 10 cycles, carbon recovery of 48% ± 1%, fuel utilisation of 23% ± 2%, and an average calcium oxide and iron oxide utilisation of 22% ± 1% and 11% ± 1%. These experimental performance indicators for the temperature-programmed CO production were consistently better than those of the isothermal implementation mode by 20% to 35%. Over 10 consecutive process cycles, no significant losses in CO yield were observed in either implementation mode. Process simulation was carried out for 1 million metric tonnes per year of equivalent CO_(2) emissions from the blast furnace gas of a steel mill to analyse the exergy losses in both modes of operation. Comparison of the exergy efficiency of the temperature-programmed process to the isothermal process showed that the former is more efficient because of the higher CO concentration achievable,despite 20% higher exergy losses caused by heat transfer required to change temperature.展开更多
AIM:To find out effect of different signal-to-noise ratios(SNRs) on word perception at different number of channels.METHODS: Thirty participants with normal hearing in the age range of 18-25 years(mean age 23.6 years)...AIM:To find out effect of different signal-to-noise ratios(SNRs) on word perception at different number of channels.METHODS: Thirty participants with normal hearing in the age range of 18-25 years(mean age 23.6 years) were involved in the study. For word perception test, there were 28 key-words embedded in sentences comprises of four lists processed for different channels(4, 8 and 32 channel) using AngelS im program at-5, 0 and +5 SNRs. The recorded stimuli were routed through audiometer connected with computer with CD player and presented in free field condition with speakers kept at 0° azimuth in a sound treated room.RESULTS: Repeated measure ANOVA showed significant main effect across different SNRs at 4 channel, 8 channel and at 32 channel. Further, Bonferroni multiple pairwise comparisons shows significant differences between all the possible combinations(4, 8 and 32 channel) at +5 dB SNR, 0 dB SNR and-5 dB SNR.CONCLUSION: Present study highlights the importance of more number of channels and higher signal to noise ratio for better perception of words in noise in simulated cochlear implantees.展开更多
Introduction.Vein of Galen aneurysmal malformation(VGAM)is an exceptionally rare cerebrovascular anomaly,occurring in approximately 1 in 25,000 live births.Although it represents less than 1% of all intracranial vascu...Introduction.Vein of Galen aneurysmal malformation(VGAM)is an exceptionally rare cerebrovascular anomaly,occurring in approximately 1 in 25,000 live births.Although it represents less than 1% of all intracranial vascular malformations,it accounts for nearly 30% of pediatric intracranial vascular lesions.展开更多
To editor:Neural tube defects(NTDs)are congenital anomalies that can be classified as open or closed.Open NTDs include acrania,exencephaly,anencephaly,spina bifida,craniorachischisis,encephalocele,and iniencephaly.The...To editor:Neural tube defects(NTDs)are congenital anomalies that can be classified as open or closed.Open NTDs include acrania,exencephaly,anencephaly,spina bifida,craniorachischisis,encephalocele,and iniencephaly.The acrania-exencephaly-anencephaly sequence represents a spectrum of central nervous system(CNS)malformations characterized by gross deformities of brain tissue and the absence of the cranial vault.Craniorachischisis results from congenital fissuring of the skull and vertebral column,occurring due to the failure of normal neural tube closure during primary neurulation in early CNS development.1 Failure of cranial pore closure leads to anencephaly,while failure along the spinal axis results in spinal rachischisis totalis.展开更多
基金financial support from the project Cabon4PUR which has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 768919support of Dr. Alessandro Longo for Rietveld refinement of XRDsupport of the Wim Rogiers and Micha?l Lottin at the LCT for the fixed bed reactor setup used for experimental validation of the process concept。
文摘Up to 9% of the global CO_(2) emissions come from the iron and steel industry. Here, a combined chemical looping process to produce CO, a building block for the chemical industry, from the CO_(2) -rich blast furnace gas of a steel mill is proposed. This cyclic process can make use of abundant Fe_(3)O_(4) and CaO as solid oxygen and CO_(2) carriers at atmospheric pressure. A proof of concept was obtained in a laboratory-scale fixed bed reactor with synthetic blast furnace gas and Fe_(3)O_(4) /CaO = 0.6 kg/kg. CO production from the proposed process was investigated at both isothermal conditions(1023 K) and upon imposing a temperature program from 1023 to 1148 K. The experimental results were compared using performance indicators such as CO yield, CO space time yield, carbon recovery of the process, fuel utilisation, and solids’ utilisation.The temperature-programmed CO production resulted in a CO yield of 0.056 ± 0.002 mol per mol of synthetic blast furnace gas at an average CO space time yield of 7.6 mmol kgFe^(-1) s^(-1) over 10 cycles, carbon recovery of 48% ± 1%, fuel utilisation of 23% ± 2%, and an average calcium oxide and iron oxide utilisation of 22% ± 1% and 11% ± 1%. These experimental performance indicators for the temperature-programmed CO production were consistently better than those of the isothermal implementation mode by 20% to 35%. Over 10 consecutive process cycles, no significant losses in CO yield were observed in either implementation mode. Process simulation was carried out for 1 million metric tonnes per year of equivalent CO_(2) emissions from the blast furnace gas of a steel mill to analyse the exergy losses in both modes of operation. Comparison of the exergy efficiency of the temperature-programmed process to the isothermal process showed that the former is more efficient because of the higher CO concentration achievable,despite 20% higher exergy losses caused by heat transfer required to change temperature.
文摘AIM:To find out effect of different signal-to-noise ratios(SNRs) on word perception at different number of channels.METHODS: Thirty participants with normal hearing in the age range of 18-25 years(mean age 23.6 years) were involved in the study. For word perception test, there were 28 key-words embedded in sentences comprises of four lists processed for different channels(4, 8 and 32 channel) using AngelS im program at-5, 0 and +5 SNRs. The recorded stimuli were routed through audiometer connected with computer with CD player and presented in free field condition with speakers kept at 0° azimuth in a sound treated room.RESULTS: Repeated measure ANOVA showed significant main effect across different SNRs at 4 channel, 8 channel and at 32 channel. Further, Bonferroni multiple pairwise comparisons shows significant differences between all the possible combinations(4, 8 and 32 channel) at +5 dB SNR, 0 dB SNR and-5 dB SNR.CONCLUSION: Present study highlights the importance of more number of channels and higher signal to noise ratio for better perception of words in noise in simulated cochlear implantees.
文摘Introduction.Vein of Galen aneurysmal malformation(VGAM)is an exceptionally rare cerebrovascular anomaly,occurring in approximately 1 in 25,000 live births.Although it represents less than 1% of all intracranial vascular malformations,it accounts for nearly 30% of pediatric intracranial vascular lesions.
文摘To editor:Neural tube defects(NTDs)are congenital anomalies that can be classified as open or closed.Open NTDs include acrania,exencephaly,anencephaly,spina bifida,craniorachischisis,encephalocele,and iniencephaly.The acrania-exencephaly-anencephaly sequence represents a spectrum of central nervous system(CNS)malformations characterized by gross deformities of brain tissue and the absence of the cranial vault.Craniorachischisis results from congenital fissuring of the skull and vertebral column,occurring due to the failure of normal neural tube closure during primary neurulation in early CNS development.1 Failure of cranial pore closure leads to anencephaly,while failure along the spinal axis results in spinal rachischisis totalis.
