Removal of carbonyl sulfide(COS) from CO2 stream is significant for the production and utilization of food grade CO2. This study investigates the adsorption performance of Ag/NaZSM-5 as adsorbent prepared by incipient...Removal of carbonyl sulfide(COS) from CO2 stream is significant for the production and utilization of food grade CO2. This study investigates the adsorption performance of Ag/NaZSM-5 as adsorbent prepared by incipient wetness impregnation for the removal of COS from a CO2 stream in a fixed-bed adsorption apparatus. Effects of various conditions on the preparation of adsorbent, adsorption and desorption were intensively examined. The results revealed that COS can be removed to below 1×10-9from a CO2stream(1000 ppm COS/CO2) using Ag/NaZSM-5(10 wt% AgNO3) with an adsorption capacity of 12.86 mg·g-1. The adsorbent can be fully regenerated using hot air at 450 C. The adsorption ability remained stable even after eight cycles of regeneration.展开更多
Adult stem cells or progenitors are essential for maintaining the normal structure and function of adult tissues （i.e., ho- meostasis）. One of the best examples is the adult intestinal epithelium which is constantly...Adult stem cells or progenitors are essential for maintaining the normal structure and function of adult tissues （i.e., ho- meostasis）. One of the best examples is the adult intestinal epithelium which is constantly renewed by the progeny of intestinal stem cells （ISCs）. The proliferation and differentiation of adult stem cells must be tightly controlled in order to maintain resident tissue homeostasis. Mis-regulation of stem cell proliferation and differentiation leads to depletion or excessive proliferation of stem cells, eventually resulting in severe diseases such as cancer （Radtke and Clevers, 2005; Morrison and Spradling, 2008）. Understanding the detailed regulatory mechanisms of stem cell proliferation and differ- entiation will shed insights into the causes of related human diseases.展开更多
文摘Removal of carbonyl sulfide(COS) from CO2 stream is significant for the production and utilization of food grade CO2. This study investigates the adsorption performance of Ag/NaZSM-5 as adsorbent prepared by incipient wetness impregnation for the removal of COS from a CO2 stream in a fixed-bed adsorption apparatus. Effects of various conditions on the preparation of adsorbent, adsorption and desorption were intensively examined. The results revealed that COS can be removed to below 1×10-9from a CO2stream(1000 ppm COS/CO2) using Ag/NaZSM-5(10 wt% AgNO3) with an adsorption capacity of 12.86 mg·g-1. The adsorbent can be fully regenerated using hot air at 450 C. The adsorption ability remained stable even after eight cycles of regeneration.
基金supported by the grants from the National Natural Science Foundation of China (Nos.31271582 and 31200213)China Postdoctoral Science Foundation (No.2012M510410)Beijing Scientific Research Foundation for Scholars Returned from Overseas,and Beijing Municipal Commission of Education (No.010135336400)
文摘Adult stem cells or progenitors are essential for maintaining the normal structure and function of adult tissues （i.e., ho- meostasis）. One of the best examples is the adult intestinal epithelium which is constantly renewed by the progeny of intestinal stem cells （ISCs）. The proliferation and differentiation of adult stem cells must be tightly controlled in order to maintain resident tissue homeostasis. Mis-regulation of stem cell proliferation and differentiation leads to depletion or excessive proliferation of stem cells, eventually resulting in severe diseases such as cancer （Radtke and Clevers, 2005; Morrison and Spradling, 2008）. Understanding the detailed regulatory mechanisms of stem cell proliferation and differ- entiation will shed insights into the causes of related human diseases.
